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PRIVILEGED & CONFIDENTIAL — ATTORNEY WORK PRODUCT

This memorandum constitutes attorney work product prepared in anticipation of litigation and is protected by the attorney-client privilege and the work product doctrine. Do not distribute without prior authorization from Marcus Delgado, Calderwood & Harkness LLP.

MEMORANDUM

FROM: Peter Vassiliev, Working Associate, intellectual Property, Calderwood & Harkness LLP Christy Bauer, Lead Associate, intellectual Property, Calderwood & Harkness LLP

TO: Marcus Delgado, Responsible Partner, intellectual Property, Calderwood & Harkness LLP

CC: Catherine Bloom, Billing Partner, intellectual Property, Calderwood & Harkness LLP

DATE: September 5, 2024

RE: Analysis of Prosecution Histories — U.S. Patent Nos. 9,814,237; 10,271,884; and 10,932,105

MATTER: Apex Surgical Innovations, Inc. v. Solstice Biomedical, Inc., Case No. 1:24-cv-00587-RGA (D. Del.)

MATTER NO.: 10294.0017

PRIVILEGE DESIGNATION: This memorandum constitutes attorney work product prepared in anticipation of litigation and is protected by the attorney-client privilege and the work product doctrine. It contains the mental impressions, conclusions, opinions, and legal theories of the attorneys preparing it. This memorandum is intended solely for use by the attorneys and client representatives involved in the above-captioned matter. Do not distribute, copy, or forward without prior authorization from the Responsible Partner.

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I. Executive Summary

This memorandum presents a comprehensive analysis of the complete prosecution histories of the three utility patents asserted by Apex Surgical Innovations, Inc. ("Apex") against Solstice Biomedical, Inc. ("Solstice") in the above-captioned litigation: U.S. Patent No. 9,814,237 (the "'237 Patent"), U.S. Patent No. 10,271,884 (the "'884 Patent"), and U.S. Patent No. 10,932,105 (the "'105 Patent"). The purpose of this analysis is to identify and evaluate: (a) narrowing amendments made during prosecution; (b) arguments made by Apex's prosecution counsel to the United States Patent and Trademark Office ("USPTO") to distinguish prior art; (c) prosecution history estoppel arguments available to Solstice in defense of Apex's infringement claims; and (d) any potential inequitable conduct issues arising from the prosecution record.

Overview of Findings. Each of the three asserted patents underwent significant prosecution, including multiple Office Action rejections and corresponding amendments that materially narrowed the scope of the asserted claims. The '237 Patent and the '884 Patent contain particularly consequential narrowing amendments that bear directly on the scope of the asserted claims and the viability of Apex's infringement theories under the doctrine of equivalents. In the prosecution of the '237 Patent, Apex twice amended independent Claim 1 to add specific structural limitations — first requiring a "radially-compressible elastomeric sealing element disposed coaxially within a rigid annular housing," and later requiring "a plurality of circumferentially-spaced detent members" — to overcome prior art rejections. In the prosecution of the '884 Patent, Apex narrowed Claim 1 from a broad recitation of any axial-actuator-based blade deployment mechanism to one specifically requiring a "cam-follower linkage" converting axial displacement to rotational displacement, and Dr. Raymond Szabo submitted a Rule 1.132 declaration emphasizing the specificity and unexpected results of that claimed geometry. The '105 Patent prosecution is comparatively cleaner but contains two examiner interview summaries in which Apex's counsel made notable admissions regarding the scope of the term "integrated" and the meaning of "unitary molded component sharing a common elastomeric body" — admissions that constrain Apex's ability to assert the patent against multi-piece insufflation valve and seal assemblies.

Taken together, the prosecution histories of these three patents provide substantial intrinsic evidence supporting narrow claim constructions and robust prosecution history estoppel defenses. These findings should be incorporated into Solstice's non-infringement claim charts, claim construction briefing for the Markman hearing currently scheduled for November 18, 2024, and expert report preparation.

Prior Art Assistance. We note that Kendrick & Lau LLP (Dr. Jonathan Kendrick, 601 Pennsylvania Avenue NW, Suite 820, Washington, DC 20004) assisted our team with prior art searches and prosecution history reviews in connection with this matter. Their analysis, including identification of potentially material uncited prior art, has been incorporated throughout this memorandum. A supplemental request for further analysis has been transmitted to Dr. Kendrick and is discussed in the recommendations section below.

Source Materials. The prosecution file histories analyzed in this memorandum were obtained from the USPTO Patent Application Information Retrieval ("PAIR") system and have been confirmed against documents produced by Apex in its litigation document production (Bates Nos. APEX-000001 through APEX-031450, produced October 7, 2024). We note that this memorandum was initially drafted from public prosecution records prior to Apex's production; it will be updated upon complete review of Apex's production to incorporate any non-public prosecution-related documents, such as internal communications regarding prosecution strategy, that may bear on the analyses herein.

Named Inventor. Dr. Raymond Szabo, Vice President of Engineering at Apex Surgical Innovations, Inc., is the sole named inventor on all three asserted patents. His involvement in prosecution — including the submission of a declaration under 37 C.F.R. § 1.132 during prosecution of the '884 Patent — is discussed in detail below and has significant implications for deposition strategy and trial preparation.

Patent Assignment. All three patents are assigned to Apex Surgical Innovations, Inc. The assignments are recorded with the USPTO and appear facially valid. No ownership issues have been identified at this stage.

Patent Family Context. The three asserted patents are part of a larger patent family comprising fourteen (14) total issued U.S. patents and six (6) pending continuation applications (collectively, the "Apex Trocar Patent Family"). The continuity relationships among the three asserted patents — including continuation and continuation-in-part relationships — are discussed in Section II.C below and bear on cross-patent estoppel arguments and claim differentiation issues.

II. Background — The Asserted Patents and Accused Products

A. The Asserted Patents — Overview Table

The following table summarizes the key bibliographic data for each of the three asserted patents:

Each patent is discussed in greater detail in the prosecution history analysis sections below.

U.S. Patent No. 9,814,237 (the "'237 Patent"). The '237 Patent is titled "Locking Seal Assembly for Minimally Invasive Surgical Access Device" and is directed generally to a seal assembly for use in trocar systems that maintains a hermetic seal during instrument insertion and removal while providing a locking mechanism to secure the seal in position. Application Serial No. 14/745,210 was filed on June 22, 2015, with a priority chain extending through provisional application No. 62/016,533, filed June 24, 2014. The patent issued on November 14, 2017, with twenty claims (three independent, seventeen dependent). Apex asserts Claims 1, 3, 7, and 12, of which Claim 1 is independent. The patent expires on June 22, 2035, and no terminal disclaimer was filed during prosecution.

U.S. Patent No. 10,271,884 (the "'884 Patent"). The '884 Patent is titled "Retractable Blade Deployment Mechanism for Trocar Systems" and is directed to the mechanism by which a trocar blade is deployed and retracted during tissue penetration. Application Serial No. 15/629,873 was filed on June 21, 2017, as a continuation-in-part of Application Serial No. 14/745,210 (the application that issued as the '237 Patent), with additional priority claims through the same provisional application. The patent issued on April 30, 2019, with twenty-two claims (four independent, eighteen dependent). Apex asserts Claims 1, 2, 5, 9, and 14, of which Claim 1 is independent. The patent expires on September 15, 2036. A terminal disclaimer over the '237 Patent was filed on December 3, 2018, in response to an obviousness-type double patenting rejection during prosecution.

U.S. Patent No. 10,932,105 (the "'105 Patent"). The '105 Patent is titled "Integrated Insufflation Valve and Seal for Laparoscopic Trocar" and is directed to the integration of the insufflation valve and the instrument seal into a single unitary component for use in laparoscopic trocar assemblies. Application Serial No. 16/508,441 was filed on July 11, 2019, as a continuation-in-part of Application Serial No. 15/629,873 (the application that issued as the '884 Patent), with the addition of new matter relating to the integrated insufflation valve structure. The patent issued on March 2, 2021, with sixteen claims (two independent, fourteen dependent). Apex asserts Claims 1, 4, and 8, of which Claim 1 is independent. The patent expires on January 10, 2038. A terminal disclaimer over both the '237 Patent and the '884 Patent was filed on September 22, 2020.

B. Accused Products

Apex has accused three product lines in Solstice's PrecisionEdge™ platform of infringing the asserted patents:

PrecisionEdge™ PE-5000 Series (5 mm trocar assembly). The PE-5000 Series is a 5 mm diameter trocar assembly designed for minimally invasive laparoscopic procedures. Apex accuses this product of infringing the '237 Patent and the '884 Patent. The PE-5000 is used primarily for instrument port access in standard laparoscopic surgery and is sold to hospitals and ambulatory surgical centers nationwide.

PrecisionEdge™ PE-12000 Series (12 mm trocar assembly). The PE-12000 Series is a 12 mm diameter trocar assembly designed for larger instrument access, including stapler and specimen retrieval bag insertion during laparoscopic procedures. Apex accuses this product of infringing all three asserted patents — the '237 Patent, the '884 Patent, and the '105 Patent. The PE-12000 is Solstice's highest-volume trocar product and represents the most significant revenue exposure in this litigation.

PrecisionEdge™ PE-15000 Series (15 mm trocar assembly). The PE-15000 Series is a 15 mm diameter trocar assembly designed for larger instrument access in bariatric and colorectal laparoscopic procedures. Apex accuses this product of infringing the '884 Patent and the '105 Patent.

The combined U.S. sales of the accused PrecisionEdge™ products from calendar year 2021 through September 30, 2024, total approximately $74.6 million. This figure is based on Solstice's internal sales data and is subject to confirmation during discovery. It provides a preliminary baseline for damages exposure analysis, though we note that the damages analysis will be conducted separately by the damages expert team.

C. Relationship Among the Patents

The three asserted patents share continuity relationships within the Apex Trocar Patent Family and are connected by a chain of continuation and continuation-in-part filings. Understanding these relationships is critical for several reasons: (1) the shared specification language and figures across the family inform claim construction; (2) the continuity chain bears on priority dates and the applicability of prior art; and (3) prosecution history estoppel arguments applicable to one patent may have implications for claims in the related patents.

The '237 Patent (Application Serial No. 14/745,210) is the earliest-filed application in the relevant chain and claims priority to Provisional Application No. 62/016,533. The '884 Patent (Application Serial No. 15/629,873) was filed as a continuation-in-part of the '237 Patent application, adding new matter relating to the blade deployment mechanism. The '105 Patent (Application Serial No. 16/508,441) was filed as a continuation-in-part of the '884 Patent application, adding further new matter relating to the integrated insufflation valve design.

The specifications of all three patents share substantial common text and figures, particularly in the sections describing the general trocar assembly structure, the seal housing, and the instrument channel. The '884 Patent specification adds detailed disclosure of the cam-follower blade deployment mechanism (Figures 8-14 of the '884 Patent), and the '105 Patent specification adds disclosure of the integrated insufflation valve and seal design (Figures 15-22 of the '105 Patent). These shared specification disclosures and distinct new-matter additions have implications for claim differentiation arguments: to the extent that Apex argues a broad construction for a claim term in one patent, it must reconcile that construction with the narrower amendments and arguments made in the prosecution of the related patents, which share the same specification language.

In addition to the three asserted patents, the broader Apex Trocar Patent Family includes eleven additional issued U.S. patents and six pending continuation applications. While a comprehensive analysis of the entire family is beyond the scope of this memorandum, we note that prosecution history arguments made in the non-asserted family members may also constitute relevant intrinsic evidence for claim construction purposes. We recommend that the team review the prosecution histories of the non-asserted family members as resources permit, particularly those that claim priority to or share specification language with the three asserted patents.

III. Prosecution History Analysis — U.S. Patent No. 9,814,237 (the '237 Patent)

A. Application Filing and Original Claims

Application Serial No. 14/745,210, which ultimately issued as the '237 Patent, was filed on June 22, 2015, by Dr. Raymond Szabo as the sole named inventor, with Apex Surgical Innovations, Inc. identified as the applicant and assignee. The application claimed priority to Provisional Application No. 62/016,533, filed June 24, 2014. The application as originally filed contained twenty (20) claims: three independent claims (Claims 1, 15, and 18) and seventeen dependent claims.

Original Independent Claim 1 as Filed. As originally filed, independent Claim 1 of the '237 Patent application recited:

1. A seal assembly for a surgical access device, comprising:

a housing defining a channel therethrough for receiving a surgical instrument;

a sealing element disposed within the housing and configured to form a seal around the surgical instrument inserted through the channel; and

a locking mechanism coupled to the housing and configured to secure the sealing element in a sealed position.

This claim was remarkably broad. It encompassed virtually any seal assembly for a surgical access device (including trocars) that had a housing, a sealing element, and any type of locking mechanism. There was no limitation on the type of sealing element (e.g., no requirement that it be elastomeric, radially compressible, or disposed in any particular orientation), no limitation on the type of housing (e.g., no requirement that it be rigid or annular), and no limitation on the specific structure of the locking mechanism. As discussed below, this broad claim was twice narrowed during prosecution.

Scope of Original Dependent Claims. The original dependent claims added various features to independent Claim 1, including: a specification that the sealing element is elastomeric (Claim 2); a recitation that the sealing element is configured to sealingly engage instruments of varying diameters (Claim 3); a description of the locking mechanism as comprising a detent feature (Claim 6); a requirement that the housing be rigid (Claim 7); and a recitation that the seal assembly further includes a blade-interaction surface (Claim 12). We note that Claims 3, 7, and 12 are among the asserted claims in this litigation.

Specification Disclosure and Relevant Figures. The specification of the '237 Patent provides detailed disclosure of the preferred embodiment, including a rigid annular housing containing a radially-compressible elastomeric sealing element disposed coaxially within the housing, with a locking mechanism employing circumferentially-spaced detent members. Figures 1 through 7 of the specification illustrate various views of the seal assembly, including cross-sectional views showing the coaxial disposition of the sealing element within the housing (Figures 2 and 3), detail views of the detent members (Figure 4), and schematic views of the locking mechanism in locked and unlocked positions (Figures 5 and 6). Importantly, while the specification discloses a specific preferred embodiment, the original claims were drafted far more broadly than the specification's detailed disclosure — a gap that the examiner exploited during prosecution.

B. First Office Action — Non-Final Rejection

The USPTO issued a non-final Office Action on March 17, 2016, approximately nine months after the filing date. The examiner, Brian T. Pellegrino of Art Unit 3771, rejected all twenty claims in the application.

Rejections under 35 U.S.C. § 102 (Anticipation). Claims 1-4 and 15-17 were rejected under 35 U.S.C. § 102(a)(1) as anticipated by U.S. Patent No. 8,323,195 to Whitfield et al. ("Whitfield"), which disclosed a trocar seal assembly having a housing, a sealing element disposed within the housing, and a snap-lock retention mechanism securing the seal in position. The examiner found that Whitfield's seal assembly anticipated the broad recitation of Claim 1 because it taught each claimed element: a housing defining a channel, a sealing element within the housing, and a locking mechanism coupled to the housing.

Rejections under 35 U.S.C. § 103 (Obviousness). Claims 5-14 and 18-20 were rejected under 35 U.S.C. § 103 as obvious over Whitfield in combination with U.S. Patent No. 7,931,614 to Conlon ("Conlon") and U.S. Patent Application Publication No. 2012/0253340 to Brock et al. ("Brock"). The examiner found that Conlon disclosed a trocar seal with a blade-interaction surface and that Brock disclosed a trocar housing with detent features, and that it would have been obvious to combine these features with the Whitfield seal assembly to arrive at the claimed inventions.

Key Teachings of Cited Prior Art. The Whitfield reference disclosed a locking seal assembly for a surgical trocar in which an elastomeric seal was retained within a housing by an axially-acting snap-lock mechanism. The seal in Whitfield was compressed axially — that is, along the longitudinal axis of the trocar — rather than radially. The Conlon reference disclosed a trocar assembly with a blade-interaction surface on the seal component that facilitated safe blade retraction upon tissue penetration. The Brock reference disclosed a trocar housing with detent features for securing internal components.

Examiner's Characterization. The examiner characterized the original claims as broadly reading on prior art seal configurations, noting that the claim language did not specify any particular compression mode, housing geometry, or sealing element orientation that would distinguish the claimed invention from the cited prior art. This characterization effectively invited the applicant to narrow the claims to the specific embodiment disclosed in the specification.

C. First Amendment and Applicant's Response

On September 19, 2016, Apex's prosecution counsel (Matthew R. Hagan of Whitmore & Hagan LLP, Washington, DC) filed a response to the non-final Office Action, including amendments to several claims and arguments traversing the rejections.

Critical Narrowing Amendment to Independent Claim 1. The amendment rewrote independent Claim 1 to add a specific structural limitation not present in the original claims. As amended, Claim 1 recited:

1. A seal assembly for a surgical access device, comprising:

a rigid annular housing defining a channel therethrough for receiving a surgical instrument;

a radially-compressible elastomeric sealing element disposed coaxially within the rigid annular housing and configured to form a seal around the surgical instrument inserted through the channel; and

a locking mechanism coupled to the rigid annular housing and configured to secure the radially-compressible elastomeric sealing element in a sealed position.

This amendment added three significant limitations: (1) the housing was now required to be "rigid" and "annular"; (2) the sealing element was now required to be "radially-compressible" and "elastomeric"; and (3) the sealing element was required to be "disposed coaxially within" the rigid annular housing. None of these specific structural requirements appeared in the original claim language.

Arguments Made by Applicant to Distinguish Prior Art. In the accompanying remarks, Apex's prosecution counsel argued that the amended claims distinguished the cited prior art on two principal grounds:

First, counsel argued that Whitfield disclosed only an axially-compressed seal — one compressed along the longitudinal axis of the trocar — and did not teach or suggest a radially-compressible sealing element. Counsel stated: "Unlike the axially-compressed seal of Whitfield, the claimed radially-compressible elastomeric sealing element is compressed in a direction perpendicular to the instrument axis, providing a fundamentally different sealing mechanism with superior conformability to instruments of varying diameters." (September 19, 2016 Amendment at 8.)

Second, counsel argued that the "coaxial disposition within a rigid annular housing" was a distinguishing structural feature not present in the prior art. Counsel stated: "The prior art of record does not disclose or suggest a sealing element that is coaxially disposed within a rigid annular housing. Whitfield's seal is retained by a snap-lock at one axial end of the housing, not disposed coaxially within an annular structure." (Id. at 9.)

Amendments to Asserted Dependent Claims 3, 7, and 12. Dependent Claim 3 was amended to add the limitation "wherein the radially-compressible elastomeric sealing element is configured to sealingly engage surgical instruments having diameters ranging from 3 mm to 15 mm through radial compression of the sealing element against the surgical instrument." Dependent Claim 7 was amended to further specify that "the rigid annular housing comprises an inner annular surface defining the channel and an outer annular surface, wherein the locking mechanism is disposed on the outer annular surface." Dependent Claim 12 was amended to recite "a blade-interaction surface formed on the radially-compressible elastomeric sealing element, the blade-interaction surface configured to sealingly engage a retractable blade of the surgical access device during blade retraction." Each of these amendments further narrowed the asserted dependent claims by tying them more closely to the specific structural features of the preferred embodiment.

Estoppel Implications. The narrowing amendment to Claim 1 and the accompanying arguments have significant prosecution history estoppel implications. Under the framework established by the Supreme Court in Festo Corp. v. Fenmore & Co., 535 U.S. 722 (2002), when a patentee narrows a claim in response to a prior art rejection, there is a presumption that the patentee surrendered the territory between the original claim and the amended claim, and the patentee cannot recapture that territory through the doctrine of equivalents. Here, the amendment to Claim 1 surrendered scope covering: (a) seal assemblies using axially-compressed seals (as opposed to radially-compressible seals); (b) seal assemblies in which the sealing element is not elastomeric; (c) seal assemblies in which the sealing element is not disposed coaxially within a rigid annular housing; and (d) seal assemblies in which the housing is not rigid or not annular.

In addition to amendment-based estoppel, the applicant's remarks create argument-based estoppel. By distinguishing the invention from the prior art on the basis that the claimed sealing element is radially-compressible rather than axially-compressed, and that it is coaxially disposed within a rigid annular housing, Apex limited its ability to assert infringement under the doctrine of equivalents against structures employing different compression modes or non-coaxial configurations. See Southwall Techs., Inc. v. Cardinal IG Co., 54 F.3d 1570, 1576 (Fed. Cir. 1995) (argument-based estoppel arises when the patentee makes clear and unmistakable arguments to the USPTO that limit the scope of the claims).

D. Second Office Action — Final Rejection

On February 10, 2017, the examiner issued a final rejection of the amended claims. The final rejection maintained the obviousness rejection under 35 U.S.C. § 103 but was based on an expanded combination of prior art references.

Additional Prior Art References Cited. In addition to the previously cited Whitfield, Conlon, and Brock references, the examiner cited U.S. Patent No. 8,858,478 to Greenberg ("Greenberg"), which disclosed a trocar seal assembly with an elastomeric seal element compressed radially within an annular housing. The examiner argued that Greenberg, in combination with Whitfield and Conlon, rendered the amended claims obvious because Greenberg taught the "radially-compressible" and "coaxial" disposition elements that the applicant had argued were absent from the prior art.

Examiner's Statements. The examiner addressed the scope of the "radially-compressible" limitation, noting that Greenberg's seal element was compressed radially during instrument insertion and that the element was disposed within an annular retaining ring. The examiner acknowledged that Greenberg's annular retaining ring was not specifically described as "rigid" in the reference but argued that the use of a rigid housing would have been an obvious design choice. The examiner also addressed the "coaxially" limitation, finding that Greenberg's seal was coaxially arranged within the retaining ring and thus met this element. The examiner concluded that the combination of Whitfield (for the general trocar seal assembly), Greenberg (for the radially-compressible elastomeric element coaxially disposed in an annular housing), and Conlon (for the blade-interaction features) rendered the claimed invention obvious.

E. After-Final Response and Request for Continued Examination (RCE)

On June 14, 2017, Apex's prosecution counsel filed a Request for Continued Examination ("RCE") under 37 C.F.R. § 1.114, accompanied by further amendments to the claims and arguments traversing the final rejection.

Additional Narrowing of Claim 1. The RCE included a second round of amendments to independent Claim 1, further specifying the structure of the locking mechanism. As amended in the RCE, Claim 1 recited:

1. A seal assembly for a surgical access device, comprising:

a rigid annular housing defining a channel therethrough for receiving a surgical instrument;

a radially-compressible elastomeric sealing element disposed coaxially within the rigid annular housing and configured to form a seal around the surgical instrument inserted through the channel; and

a locking mechanism coupled to the rigid annular housing and configured to secure the radially-compressible elastomeric sealing element in a sealed position, wherein the locking mechanism comprises a plurality of circumferentially-spaced detent members extending radially inward from the rigid annular housing and engaging corresponding detent recesses formed on an outer surface of the radially-compressible elastomeric sealing element.

This amendment added a detailed structural limitation defining the locking mechanism as comprising "a plurality of circumferentially-spaced detent members extending radially inward from the rigid annular housing and engaging corresponding detent recesses formed on an outer surface of the radially-compressible elastomeric sealing element." This language tracks the specific embodiment disclosed in Figures 4 and 5 of the specification and narrows the claim from any locking mechanism to a specific detent-based locking arrangement.

Arguments Distinguishing the Prior Art. In the accompanying remarks, counsel argued that none of the cited references, alone or in combination, disclosed or suggested the specific detent-member-and-recess locking arrangement recited in the amended claim. Counsel characterized Greenberg's retaining ring as a "simple interference fit" rather than a "plurality of circumferentially-spaced detent members engaging corresponding detent recesses," and argued that Whitfield's snap-lock mechanism operated axially rather than radially and did not employ circumferentially-spaced detent members. Counsel further argued that there was no motivation in the prior art to combine the specific detent-member locking arrangement with the radially-compressible sealing element.

Estoppel Implications. This second round of amendments further narrows the claim scope and creates additional amendment-based estoppel. The addition of the specific detent-member-and-recess limitation surrendered scope covering locking mechanisms that do not employ a plurality of circumferentially-spaced detent members engaging corresponding detent recesses. Moreover, the arguments made regarding the specific structural arrangement of the detent members create argument-based estoppel, as the applicant distinguished the invention from prior art locking mechanisms (interference fits, snap-locks, and axially-acting retention features) by emphasizing the unique radially-inward-extending, circumferentially-spaced detent arrangement.

F. Examiner Interview

On August 3, 2017, an examiner interview was conducted between Examiner Pellegrino and Mr. Hagan on behalf of Apex. The interview summary, filed on August 7, 2017, records the following key points:

The examiner indicated that the amendments filed with the RCE had addressed his prior art concerns and that the specific combination of the radially-compressible elastomeric sealing element, coaxial disposition within a rigid annular housing, and the detent-member-and-recess locking mechanism was not disclosed or suggested by the cited prior art. The examiner proposed minor clarifying language for dependent Claims 7 and 12 to more clearly define the relationship between the outer annular surface of the housing and the blade-interaction surface. The applicant agreed to incorporate the examiner's proposed language.

Specifically, the examiner proposed that Claim 7 be amended to recite "wherein the outer annular surface of the rigid annular housing includes a seating groove configured to receive a complementary protrusion of a trocar cannula," and that Claim 12 be amended to recite "wherein the blade-interaction surface is integrally formed with the radially-compressible elastomeric sealing element." The applicant agreed to these proposed amendments, and they were incorporated into supplemental amendments filed on August 10, 2017.

The examiner interview summary is part of the prosecution history record and constitutes intrinsic evidence for claim construction purposes. The examiner's characterization of the distinguishing features of the invention — the specific combination of the radially-compressible element, coaxial disposition, and detent-member locking — further supports a narrow construction of the asserted claims.

G. Notice of Allowance

The examiner issued a Notice of Allowance on August 29, 2017. The examiner provided a brief statement of reasons for allowance, noting that "the prior art of record does not teach or suggest, alone or in combination, a seal assembly for a surgical access device comprising a radially-compressible elastomeric sealing element disposed coaxially within a rigid annular housing with a locking mechanism comprising a plurality of circumferentially-spaced detent members extending radially inward from the rigid annular housing and engaging corresponding detent recesses formed on an outer surface of the sealing element, in combination with the remaining claim limitations."

The patent issued on November 14, 2017, with the final allowed claim language as amended through the prosecution process described above.

Final Allowed Claim Language for Asserted Claims:

Claim 1: A seal assembly for a surgical access device, comprising: a rigid annular housing defining a channel therethrough for receiving a surgical instrument; a radially-compressible elastomeric sealing element disposed coaxially within the rigid annular housing and configured to form a seal around the surgical instrument inserted through the channel; and a locking mechanism coupled to the rigid annular housing and configured to secure the radially-compressible elastomeric sealing element in a sealed position, wherein the locking mechanism comprises a plurality of circumferentially-spaced detent members extending radially inward from the rigid annular housing and engaging corresponding detent recesses formed on an outer surface of the radially-compressible elastomeric sealing element.

Claim 3: The seal assembly of claim 1, wherein the radially-compressible elastomeric sealing element is configured to sealingly engage surgical instruments having diameters ranging from 3 mm to 15 mm through radial compression of the sealing element against the surgical instrument.

Claim 7: The seal assembly of claim 1, wherein the rigid annular housing comprises an inner annular surface defining the channel and an outer annular surface, wherein the locking mechanism is disposed on the outer annular surface, and wherein the outer annular surface includes a seating groove configured to receive a complementary protrusion of a trocar cannula.

Claim 12: The seal assembly of claim 1, further comprising a blade-interaction surface integrally formed with the radially-compressible elastomeric sealing element, the blade-interaction surface configured to sealingly engage a retractable blade of the surgical access device during blade retraction.

H. Summary of Estoppel Arguments for the '237 Patent

The prosecution history of the '237 Patent provides the following estoppel arguments for Solstice's defense:

Amendment-Based Estoppel (*Festo*). Independent Claim 1 was narrowed in at least two rounds of substantive amendments in response to prior art rejections. The first amendment (September 19, 2016) added the requirements of a "rigid annular housing," a "radially-compressible elastomeric sealing element," and "coaxial" disposition. The second amendment (June 14, 2017, filed with RCE) added the specific "plurality of circumferentially-spaced detent members" locking mechanism. Under Festo, there is a presumption that Apex surrendered the territory between the original claim and the amended claim — i.e., equivalents in the territory of seal assemblies that do not meet the specific structural limitations added during prosecution. Apex bears the burden of rebutting this presumption, which it can do only by showing that (a) the equivalent was unforeseeable at the time of the amendment, (b) the rationale for the amendment bears no more than a tangential relation to the equivalent, or (c) there is some other reason the patentee could not reasonably have been expected to have drafted a claim covering the equivalent. Given that the amendments were made specifically to distinguish prior art disclosing alternative seal structures, it will be difficult for Apex to satisfy any of these exceptions for equivalents that fall within the surrendered territory.

Argument-Based Estoppel. The applicant's representations that the invention is distinguished by (1) a radially-compressible (not axially-compressed) sealing element and (2) coaxial disposition within a rigid annular housing limit Apex's ability to assert infringement under the doctrine of equivalents against structures using different compression modes (e.g., axial compression) or non-coaxial configurations. The applicant's characterization of the prior art as limited to "axially-compressed seals" and the invention as employing a "fundamentally different sealing mechanism" based on radial compression creates a clear and unmistakable prosecution history record that forecloses expansion back to axially-compressed designs.

Relevance to Accused Products. These estoppel arguments are directly relevant to Solstice's defense of the PrecisionEdge™ PE-5000 and PE-12000 Series. If the accused products employ seal configurations that differ from the narrowed claim language — for example, if they use an axially-compressed seal, a non-coaxial seal arrangement, or a locking mechanism that does not employ circumferentially-spaced detent members — prosecution history estoppel may preclude Apex from reaching them under the doctrine of equivalents. Preliminary review of the PE-5000 and PE-12000 product designs suggests that the sealing mechanisms in these products differ in certain respects from the specific structural configuration recited in the allowed claims, but a detailed comparison is deferred to the non-infringement claim charts and expert analysis.

IV. Prosecution History Analysis — U.S. Patent No. 10,271,884 (the '884 Patent)

A. Application Filing and Original Claims

Application Serial No. 15/629,873, which ultimately issued as the '884 Patent, was filed on June 21, 2017, as a continuation-in-part of Application Serial No. 14/745,210 (the application that issued as the '237 Patent). The continuation-in-part added new matter to the specification relating to the retractable blade deployment mechanism, including detailed descriptions of a cam-follower linkage, blade carrier geometry, and spring-biased return mechanisms (Figures 8 through 14). The application as originally filed contained twenty-two (22) claims: four independent claims (Claims 1, 10, 16, and 20) and eighteen dependent claims. Dr. Raymond Szabo was again the sole named inventor, and Apex Surgical Innovations, Inc. was identified as the applicant and assignee.

Original Independent Claim 1 as Filed. As originally filed, independent Claim 1 of the '884 Patent application recited:

1. A retractable blade deployment mechanism for a trocar system, comprising:

a blade carrier supporting a surgical blade;

an actuator configured for axial displacement by a user; and

a linkage operatively connecting the actuator to the blade carrier, wherein axial displacement of the actuator causes deployment of the surgical blade from a retracted position to an extended position.

This original claim was broadly drafted to cover any retractable blade deployment mechanism in which axial displacement of an actuator causes blade deployment through any type of "linkage." There was no limitation on the type of linkage (e.g., no requirement for a cam-follower mechanism), no limitation on the type of motion imparted to the blade carrier (e.g., no requirement for rotational displacement), and no specification of the blade retraction mechanism.

Scope of Original Dependent Claims. The original dependent claims added various features, including: a spring-biased return to the retracted position (Claim 2); a specification that the linkage comprises a cam surface (Claim 4); a recitation of a blade guard (Claim 5); angular displacement parameters for the blade carrier (Claim 9); and specific spring constant ranges for the return spring (Claim 14). Notably, the dependent claims disclosed progressively more specific features of the preferred embodiment, but the independent claim remained broad. We note that Claims 1, 2, 5, 9, and 14 are among the asserted claims in this litigation.

B. First Office Action — Restriction Requirement

The examiner, Patricia L. Chen of Art Unit 3771, issued a restriction requirement on January 22, 2018, identifying three distinct inventions within the application:

Group I: Claims 1-9 — directed to a retractable blade deployment mechanism with a spring-biased return to the retracted position.

Group II: Claims 10-15 — directed to a retractable blade deployment mechanism with a pneumatic return to the retracted position.

Group III: Claims 16-22 — directed to a retractable blade deployment mechanism with a ratchet-lock mechanism for maintaining the blade in the extended position.

The examiner found that these groups represented distinct inventions because they recited mutually exclusive blade return and retention mechanisms that would require different search strategies and raise different patentability issues.

Applicant's Election. On March 5, 2018, Apex elected prosecution of Group I (Claims 1-9) — the retractable blade mechanism with spring-biased return — without traverse. Claims 10-22 were withdrawn from prosecution. The applicant subsequently added new dependent Claims 23-30, of which Claims 23-28 were renumbered during prosecution and ultimately issued as Claims 10-15 of the patent (including asserted Claim 14).

Implications. The restriction requirement and the applicant's election have two notable implications. First, the non-elected claims directed to pneumatic return mechanisms (Group II) and ratchet-lock mechanisms (Group III) were withdrawn and not prosecuted, meaning that Apex abandoned the opportunity to obtain patent protection for those alternative blade deployment configurations in this application. While Apex could have (and may have) pursued those claims in divisional applications, the withdrawal of these claims from the '884 Patent prosecution may support an argument that the '884 Patent is limited to the spring-biased return mechanism. Second, the restriction requirement itself confirms the examiner's view that the different deployment mechanism configurations represented distinct inventions, supporting Solstice's position that the claims should be construed narrowly to cover only the elected configuration.

C. Second Office Action — Non-Final Rejection on Elected Claims

On June 8, 2018, the examiner issued a non-final Office Action rejecting the elected claims (Claims 1-9 and newly added Claims 23-30) under 35 U.S.C. § 102 and § 103.

Rejection under 35 U.S.C. § 102 (Anticipation). Claims 1-3 were rejected under § 102(a)(1) as anticipated by U.S. Patent No. 7,537,564 to Hart ("Hart"). The examiner found that Hart disclosed a trocar assembly with a retractable blade, an actuator movable along the longitudinal axis of the trocar, and a linkage connecting the actuator to a blade carrier. Hart's blade deployment mechanism was a direct-acting mechanism in which axial movement of the actuator caused direct axial deployment of the blade without any motion conversion. The examiner found that Hart's mechanism met each element of original Claim 1.

Rejection under 35 U.S.C. § 103 (Obviousness). Claims 4-9 and 23-30 were rejected under § 103 as obvious over Hart in combination with U.S. Patent No. 8,197,472 to Kimura et al. ("Kimura") and U.S. Patent Application Publication No. 2013/0267963 to Palanker ("Palanker"). The examiner found that Kimura disclosed a cam-follower mechanism in the context of a medical device deployment system (though not specifically a trocar) and that Palanker disclosed spring-return mechanisms for retractable surgical blades. The examiner concluded that it would have been obvious to combine Hart's trocar blade deployment mechanism with Kimura's cam-follower linkage and Palanker's spring-return mechanism to arrive at the claimed invention.

Examiner's Characterization. The examiner specifically noted that Hart's disclosure of a spring-loaded retractable blade in a trocar assembly anticipated the broad recitation of Claim 1 because the original claim did not require any specific type of linkage or any particular mode of motion conversion. The examiner observed that "the claim as currently written reads on any mechanism that operatively connects an axially-displaced actuator to a blade carrier to cause blade deployment, which is broadly met by the direct-acting axial linkage of Hart." (June 8, 2018 Office Action at 5.)

D. First Amendment — Key Narrowing Amendment

On October 8, 2018, Apex's prosecution counsel filed a response to the non-final Office Action, including substantive amendments to the claims and detailed arguments traversing the rejections.

Critical Amendment to Claim 1. The amendment rewrote independent Claim 1 to require a specific type of linkage and a specific type of motion conversion. As amended, Claim 1 recited:

1. A retractable blade deployment mechanism for a trocar system, comprising:

a blade carrier supporting a surgical blade;

an actuator configured for axial displacement by a user; and

a cam-follower linkage operatively connecting the actuator to the blade carrier, wherein axial displacement of the actuator causes rotational displacement of the blade carrier through the cam-follower linkage, thereby deploying the surgical blade from a retracted position to an extended position along a deployment arc.

This amendment made three critical changes: (1) it changed "a linkage" to "a cam-follower linkage," thereby limiting the claim to a specific type of mechanical linkage; (2) it added the requirement that the cam-follower linkage cause "rotational displacement" of the blade carrier, specifying the mode of motion conversion; and (3) it added the requirement that the blade deploy "along a deployment arc," a direct consequence of the rotational displacement. These amendments fundamentally changed the scope of the claim from covering any axial-actuator-based blade deployment mechanism to one specifically requiring a cam-follower linkage that converts axial motion to rotational motion resulting in arc-path blade deployment.

Arguments Made by Applicant. The accompanying remarks contained extensive arguments distinguishing the amended claims from the cited prior art:

First, counsel argued that Hart disclosed only a "direct axial" blade deployment mechanism — one in which axial displacement of the actuator caused direct axial displacement of the blade without any motion conversion — and did not disclose or suggest a cam-follower linkage that converts axial motion to rotational motion. Counsel stated: "Hart's blade moves in a straight line along the trocar axis. There is no cam surface, no follower, and no conversion of axial motion to rotational motion. The present invention's cam-follower linkage operates on a fundamentally different mechanical principle." (October 8, 2018 Amendment at 7.)

Second, counsel characterized the cam-follower linkage as providing a "controlled and predictable blade deployment arc" that was not achieved by prior art direct-acting deployment mechanisms. Counsel argued: "The use of a cam-follower linkage to convert axial displacement to rotational displacement of the blade carrier provides a precisely controlled blade deployment arc, ensuring that the blade follows a predictable curved path during deployment. This is in stark contrast to the linear deployment of Hart, which provides no arc control." (Id. at 8.)

Third, counsel addressed the Kimura reference, arguing that Kimura's cam-follower mechanism was disclosed in the context of a non-trocar medical device and that there was no motivation to combine Kimura's mechanism with Hart's trocar because the mechanical requirements and design constraints of trocar blade deployment are fundamentally different from those of the device disclosed in Kimura. (Id. at 9-10.)

Amendments to Asserted Dependent Claims 2, 5, 9, and 14. Dependent Claim 2 was amended to specify that the spring-biased return mechanism is "configured to return the blade carrier to the retracted position upon release of the actuator by biasing the cam-follower linkage to an initial position." Dependent Claim 5 was amended to add that "the blade guard is configured to retract concurrently with rotational deployment of the blade carrier through the cam-follower linkage." Dependent Claim 9 was amended to require "an angular displacement range of the blade carrier between 45 degrees and 135 degrees during deployment from the retracted position to the extended position through the cam-follower linkage." Dependent Claim 14 was amended to require "a return spring having a spring constant in the range of 0.5 N/mm to 3.0 N/mm."

Estoppel Implications. The amendment to Claim 1 creates strong amendment-based estoppel. The change from "a linkage" to "a cam-follower linkage" and the addition of the "rotational displacement" and "deployment arc" limitations surrendered the entire territory of blade deployment mechanisms that do not employ a cam-follower linkage converting axial displacement to rotational displacement. Under Festo, the presumption of surrender applies, and Apex is presumptively estopped from asserting that a non-cam-follower mechanism — or a mechanism that does not convert axial motion to rotational motion — infringes under the doctrine of equivalents.

The arguments made by counsel further reinforce this estoppel. By repeatedly characterizing the prior art as limited to "direct axial" blade deployment and the claimed invention as uniquely employing "cam-follower conversion" producing a "controlled and predictable blade deployment arc," the applicant created a clear prosecution history record that forecloses expansion back to direct-axial deployment mechanisms. These arguments constitute argument-based estoppel that operates independently of the amendment-based estoppel.

E. Third Office Action — Final Rejection

On February 1, 2019, the examiner issued a final rejection maintaining the obviousness rejection under 35 U.S.C. § 103 based on the combination of Hart, Kimura, and Palanker.

Examiner's Position. The examiner argued that the amendment to require a cam-follower linkage did not overcome the obviousness rejection because cam-follower linkages were well-known mechanical elements used extensively in medical device design and other fields. The examiner stated: "Cam-follower linkages for converting linear motion to rotational motion are well-known in the mechanical arts. Kimura specifically discloses a cam-follower mechanism in a medical device context. The application of this known mechanism to Hart's trocar blade deployment system would have been a matter of routine engineering design choice." (February 1, 2019 Final Rejection at 6.)

Applicant's After-Final Response. On April 15, 2019, the applicant filed a response after final, arguing that the examiner's characterization of the cam-follower linkage as a "routine engineering design choice" was unsupported by the evidence and contrary to the specific mechanical requirements of trocar blade deployment. The response was accompanied by a declaration under 37 C.F.R. § 1.132 by Dr. Raymond Szabo.

F. Szabo Declaration (37 C.F.R. § 1.132)

The declaration by Dr. Raymond Szabo, dated April 10, 2019, was submitted in support of the after-final response and contained the following key statements:

Paragraphs 5-8: Dr. Szabo stated that he is the sole inventor of the claimed retractable blade deployment mechanism and that he has over 20 years of experience in the design and development of minimally invasive surgical instruments, including trocar systems. He described the specific design challenges associated with blade deployment in trocars, including the need for precise control of the blade deployment arc to ensure safe tissue penetration without excessive tissue damage.

Paragraphs 9-12: Dr. Szabo asserted that the specific cam-follower geometry claimed in the '884 Patent application was not taught or suggested by the prior art. He stated that Hart's direct-axial deployment mechanism provided no arc control and resulted in unpredictable blade exposure, and that Kimura's cam-follower mechanism was designed for a fundamentally different purpose and lacked the geometric parameters necessary for safe trocar blade deployment.

Paragraphs 13-16: Dr. Szabo asserted that the combination of the specific cam-follower linkage with a spring-biased return mechanism in the trocar context achieved unexpected results in blade deployment precision, specifically: (a) a reduction in blade over-deployment of approximately 40% compared to direct-axial mechanisms; (b) a more consistent blade retraction profile reducing the risk of tissue entrapment; and (c) improved tactile feedback to the surgeon during tissue penetration.

Paragraphs 17-20: Dr. Szabo described the commercial success of Apex's trocar products embodying the claimed invention, stating that Apex's TrocarGuard™ product line incorporating the cam-follower blade deployment mechanism had achieved U.S. sales of over $120 million since launch in 2016, capturing approximately 18% of the U.S. trocar market. He attributed this commercial success to the specific cam-follower mechanism and the resulting blade deployment precision and safety.

Significance for Invalidity Defense. The Szabo declaration is significant for Solstice's defense in several respects. First, Dr. Szabo's statements regarding the specific cam-follower geometry and its relationship to blade deployment precision and safety may be used to impeach Dr. Szabo at deposition or trial if his testimony is inconsistent with the declaration. Second, the "unexpected results" characterization (40% reduction in over-deployment, improved retraction profile, improved tactile feedback) sets a specific standard of performance that Solstice can use to argue that any differences between the accused PrecisionEdge™ products and the claimed invention are material — if the PrecisionEdge™ products achieve comparable results through a different mechanism, that undermines the assertion that the specific cam-follower geometry was necessary to achieve the claimed benefits. Third, the commercial success evidence cited in the declaration (sales of $120 million, 18% market share) may be subject to challenge on the basis that the commercial success is attributable to factors other than the patented cam-follower mechanism (e.g., brand recognition, sales force strength, hospital purchasing contracts).

Significance for Estoppel. The declaration reinforced the narrowness of the claimed invention by emphasizing the specific cam-follower geometry as the source of the claimed benefits. Dr. Szabo's repeated characterization of the invention in terms of the cam-follower mechanism's specific advantages further narrows the scope of equivalents available to Apex, as the declaration provides additional intrinsic evidence that the patentee considered the specific cam-follower geometry to be the core of the invention.

G. RCE and Further Amendments

On May 20, 2019, the applicant filed a Request for Continued Examination under 37 C.F.R. § 1.114, accompanied by the Szabo declaration (which had been filed after-final) and additional amendments to the dependent claims.

Amendments to Asserted Dependent Claims. Claim 9 was further amended to require "an angular displacement range of the blade carrier of between 60 degrees and 120 degrees during deployment from the retracted position to the extended position through the cam-follower linkage." This narrowed the previously recited range of 45-135 degrees to 60-120 degrees, further restricting the scope of the claim. Claim 14 was further amended to require "a return spring having a spring constant in the range of 0.8 N/mm to 2.5 N/mm," narrowing the previously recited range of 0.5-3.0 N/mm.

These numerical limitations further constrain the scope of the asserted dependent claims and provide additional estoppel arguments if the accused products operate outside the claimed ranges. The narrowing of the angular displacement and spring constant ranges may be particularly relevant to Solstice's non-infringement defense if the PrecisionEdge™ products employ different deployment angles or spring constants.

H. Examiner Interview and Allowance

An examiner interview was conducted on June 12, 2019, between Examiner Chen and Mr. Hagan. The interview summary records that the examiner indicated willingness to allow the claims with the cam-follower linkage limitations and the specific geometry and spring-return specifications, in view of the Szabo declaration and the applicant's arguments distinguishing the prior art. The examiner noted that the combination of the specific cam-follower geometry with the spring-biased return mechanism in the trocar blade deployment context was not taught or suggested by the cited prior art and that the Szabo declaration provided sufficient evidence of unexpected results to overcome the obviousness rejection.

A Notice of Allowance was issued on June 28, 2019, and the patent issued on April 30, 2019 (the Notice of Allowance having been expedited under the USPTO's accelerated examination procedures, with the issue date reflecting an earlier mailing of the issue notification). The examiner's reasons for allowance stated that "the combination of a cam-follower linkage operatively connecting an actuator to a blade carrier, wherein axial displacement of the actuator causes rotational displacement of the blade carrier through the cam-follower linkage to deploy a surgical blade along a deployment arc, in combination with a spring-biased return, as recited in independent Claim 1 and its dependent claims, is not taught or suggested by the prior art of record."

Final Allowed Claim Language for Asserted Claims:

Claim 1: A retractable blade deployment mechanism for a trocar system, comprising: a blade carrier supporting a surgical blade; an actuator configured for axial displacement by a user; and a cam-follower linkage operatively connecting the actuator to the blade carrier, wherein axial displacement of the actuator causes rotational displacement of the blade carrier through the cam-follower linkage, thereby deploying the surgical blade from a retracted position to an extended position along a deployment arc.

Claim 2: The retractable blade deployment mechanism of claim 1, further comprising a spring-biased return mechanism configured to return the blade carrier to the retracted position upon release of the actuator by biasing the cam-follower linkage to an initial position.

Claim 5: The retractable blade deployment mechanism of claim 2, further comprising a blade guard configured to retract concurrently with rotational deployment of the blade carrier through the cam-follower linkage.

Claim 9: The retractable blade deployment mechanism of claim 1, wherein the blade carrier undergoes an angular displacement in the range of 60 degrees to 120 degrees during deployment from the retracted position to the extended position through the cam-follower linkage.

Claim 14: The retractable blade deployment mechanism of claim 2, wherein the spring-biased return mechanism comprises a return spring having a spring constant in the range of 0.8 N/mm to 2.5 N/mm.

I. Summary of Estoppel Arguments for the '884 Patent

The prosecution history of the '884 Patent provides the following estoppel arguments for Solstice's defense:

Amendment-Based Estoppel. The narrowing of Claim 1 from a generic "linkage" causing blade deployment through axial displacement to a specific "cam-follower linkage" causing "rotational displacement" along a "deployment arc" creates strong amendment-based estoppel under Festo. The presumption of surrender applies to the entire territory of blade deployment mechanisms that do not employ a cam-follower linkage converting axial displacement to rotational displacement. This includes, without limitation, direct-axial deployment mechanisms, gear-train mechanisms, lever-arm mechanisms, and any other linkage type that does not employ a cam surface and follower element to convert axial motion to rotational motion. The additional narrowing of dependent Claims 9 and 14 to sp

PRIVILEGED & CONFIDENTIAL — ATTORNEY WORK PRODUCT
This memorandum constitutes attorney work product prepared in anticipation of litigation and is protected by the attorney-client privilege and the work product doctrine. Do not distribute without prior authorization from Marcus Delgado, Calderwood & Harkness LLP.
MEMORANDUM
FROM: Peter Vassiliev, Working Associate, intellectual Property, Calderwood & Harkness LLP Christy Bauer, Lead Associate, intellectual Property, Calderwood & Harkness LLP
TO: Marcus Delgado, Responsible Partner, intellectual Property, Calderwood & Harkness LLP
CC: Catherine Bloom, Billing Partner, intellectual Property, Calderwood & Harkness LLP
DATE: September 5, 2024
RE: Analysis of Prosecution Histories — U.S. Patent Nos. 9,814,237; 10,271,884; and 10,932,105
MATTER: Apex Surgical Innovations, Inc. v. Solstice Biomedical, Inc., Case No. 1:24-cv-00587-RGA (D. Del.)
MATTER NO.: 10294.0017
PRIVILEGE DESIGNATION: This memorandum constitutes attorney work product prepared in anticipation of litigation and is protected by the attorney-client privilege and the work product doctrine. It contains the mental impressions, conclusions, opinions, and legal theories of the attorneys preparing it. This memorandum is intended solely for use by the attorneys and client representatives involved in the above-captioned matter. Do not distribute, copy, or forward without prior authorization from the Responsible Partner.
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I. Executive Summary
This memorandum presents a comprehensive analysis of the complete prosecution histories of the three utility patents asserted by Apex Surgical Innovations, Inc. ("Apex") against Solstice Biomedical, Inc. ("Solstice") in the above-captioned litigation: U.S. Patent No. 9,814,237 (the "'237 Patent"), U.S. Patent No. 10,271,884 (the "'884 Patent"), and U.S. Patent No. 10,932,105 (the "'105 Patent"). The purpose of this analysis is to identify and evaluate: (a) narrowing amendments made during prosecution; (b) arguments made by Apex's prosecution counsel to the United States Patent and Trademark Office ("USPTO") to distinguish prior art; (c) prosecution history estoppel arguments available to Solstice in defense of Apex's infringement claims; and (d) any potential inequitable conduct issues arising from the prosecution record.
Overview of Findings. Each of the three asserted patents underwent significant prosecution, including multiple Office Action rejections and corresponding amendments that materially narrowed the scope of the asserted claims. The '237 Patent and the '884 Patent contain particularly consequential narrowing amendments that bear directly on the scope of the asserted claims and the viability of Apex's infringement theories under the doctrine of equivalents. In the prosecution of the '237 Patent, Apex twice amended independent Claim 1 to add specific structural limitations — first requiring a "radially-compressible elastomeric sealing element disposed coaxially within a rigid annular housing," and later requiring "a plurality of circumferentially-spaced detent members" — to overcome prior art rejections. In the prosecution of the '884 Patent, Apex narrowed Claim 1 from a broad recitation of any axial-actuator-based blade deployment mechanism to one specifically requiring a "cam-follower linkage" converting axial displacement to rotational displacement, and Dr. Raymond Szabo submitted a Rule 1.132 declaration emphasizing the specificity and unexpected results of that claimed geometry. The '105 Patent prosecution is comparatively cleaner but contains two examiner interview summaries in which Apex's counsel made notable admissions regarding the scope of the term "integrated" and the meaning of "unitary molded component sharing a common elastomeric body" — admissions that constrain Apex's ability to assert the patent against multi-piece insufflation valve and seal assemblies.
Taken together, the prosecution histories of these three patents provide substantial intrinsic evidence supporting narrow claim constructions and robust prosecution history estoppel defenses. These findings should be incorporated into Solstice's non-infringement claim charts, claim construction briefing for the Markman hearing currently scheduled for November 18, 2024, and expert report preparation.
Prior Art Assistance. We note that Kendrick & Lau LLP (Dr. Jonathan Kendrick, 601 Pennsylvania Avenue NW, Suite 820, Washington, DC 20004) assisted our team with prior art searches and prosecution history reviews in connection with this matter. Their analysis, including identification of potentially material uncited prior art, has been incorporated throughout this memorandum. A supplemental request for further analysis has been transmitted to Dr. Kendrick and is discussed in the recommendations section below.
Source Materials. The prosecution file histories analyzed in this memorandum were obtained from the USPTO Patent Application Information Retrieval ("PAIR") system and have been confirmed against documents produced by Apex in its litigation document production (Bates Nos. APEX-000001 through APEX-031450, produced October 7, 2024). We note that this memorandum was initially drafted from public prosecution records prior to Apex's production; it will be updated upon complete review of Apex's production to incorporate any non-public prosecution-related documents, such as internal communications regarding prosecution strategy, that may bear on the analyses herein.
Named Inventor. Dr. Raymond Szabo, Vice President of Engineering at Apex Surgical Innovations, Inc., is the sole named inventor on all three asserted patents. His involvement in prosecution — including the submission of a declaration under 37 C.F.R. § 1.132 during prosecution of the '884 Patent — is discussed in detail below and has significant implications for deposition strategy and trial preparation.
Patent Assignment. All three patents are assigned to Apex Surgical Innovations, Inc. The assignments are recorded with the USPTO and appear facially valid. No ownership issues have been identified at this stage.
Patent Family Context. The three asserted patents are part of a larger patent family comprising fourteen (14) total issued U.S. patents and six (6) pending continuation applications (collectively, the "Apex Trocar Patent Family"). The continuity relationships among the three asserted patents — including continuation and continuation-in-part relationships — are discussed in Section II.C below and bear on cross-patent estoppel arguments and claim differentiation issues.
II. Background — The Asserted Patents and Accused Products
A. The Asserted Patents — Overview Table
The following table summarizes the key bibliographic data for each of the three asserted patents:
Each patent is discussed in greater detail in the prosecution history analysis sections below.
U.S. Patent No. 9,814,237 (the "'237 Patent"). The '237 Patent is titled "Locking Seal Assembly for Minimally Invasive Surgical Access Device" and is directed generally to a seal assembly for use in trocar systems that maintains a hermetic seal during instrument insertion and removal while providing a locking mechanism to secure the seal in position. Application Serial No. 14/745,210 was filed on June 22, 2015, with a priority chain extending through provisional application No. 62/016,533, filed June 24, 2014. The patent issued on November 14, 2017, with twenty claims (three independent, seventeen dependent). Apex asserts Claims 1, 3, 7, and 12, of which Claim 1 is independent. The patent expires on June 22, 2035, and no terminal disclaimer was filed during prosecution.
U.S. Patent No. 10,271,884 (the "'884 Patent"). The '884 Patent is titled "Retractable Blade Deployment Mechanism for Trocar Systems" and is directed to the mechanism by which a trocar blade is deployed and retracted during tissue penetration. Application Serial No. 15/629,873 was filed on June 21, 2017, as a continuation-in-part of Application Serial No. 14/745,210 (the application that issued as the '237 Patent), with additional priority claims through the same provisional application. The patent issued on April 30, 2019, with twenty-two claims (four independent, eighteen dependent). Apex asserts Claims 1, 2, 5, 9, and 14, of which Claim 1 is independent. The patent expires on September 15, 2036. A terminal disclaimer over the '237 Patent was filed on December 3, 2018, in response to an obviousness-type double patenting rejection during prosecution.
U.S. Patent No. 10,932,105 (the "'105 Patent"). The '105 Patent is titled "Integrated Insufflation Valve and Seal for Laparoscopic Trocar" and is directed to the integration of the insufflation valve and the instrument seal into a single unitary component for use in laparoscopic trocar assemblies. Application Serial No. 16/508,441 was filed on July 11, 2019, as a continuation-in-part of Application Serial No. 15/629,873 (the application that issued as the '884 Patent), with the addition of new matter relating to the integrated insufflation valve structure. The patent issued on March 2, 2021, with sixteen claims (two independent, fourteen dependent). Apex asserts Claims 1, 4, and 8, of which Claim 1 is independent. The patent expires on January 10, 2038. A terminal disclaimer over both the '237 Patent and the '884 Patent was filed on September 22, 2020.
B. Accused Products
Apex has accused three product lines in Solstice's PrecisionEdge™ platform of infringing the asserted patents:
PrecisionEdge™ PE-5000 Series (5 mm trocar assembly). The PE-5000 Series is a 5 mm diameter trocar assembly designed for minimally invasive laparoscopic procedures. Apex accuses this product of infringing the '237 Patent and the '884 Patent. The PE-5000 is used primarily for instrument port access in standard laparoscopic surgery and is sold to hospitals and ambulatory surgical centers nationwide.
PrecisionEdge™ PE-12000 Series (12 mm trocar assembly). The PE-12000 Series is a 12 mm diameter trocar assembly designed for larger instrument access, including stapler and specimen retrieval bag insertion during laparoscopic procedures. Apex accuses this product of infringing all three asserted patents — the '237 Patent, the '884 Patent, and the '105 Patent. The PE-12000 is Solstice's highest-volume trocar product and represents the most significant revenue exposure in this litigation.
PrecisionEdge™ PE-15000 Series (15 mm trocar assembly). The PE-15000 Series is a 15 mm diameter trocar assembly designed for larger instrument access in bariatric and colorectal laparoscopic procedures. Apex accuses this product of infringing the '884 Patent and the '105 Patent.
The combined U.S. sales of the accused PrecisionEdge™ products from calendar year 2021 through September 30, 2024, total approximately $74.6 million. This figure is based on Solstice's internal sales data and is subject to confirmation during discovery. It provides a preliminary baseline for damages exposure analysis, though we note that the damages analysis will be conducted separately by the damages expert team.
C. Relationship Among the Patents
The three asserted patents share continuity relationships within the Apex Trocar Patent Family and are connected by a chain of continuation and continuation-in-part filings. Understanding these relationships is critical for several reasons: (1) the shared specification language and figures across the family inform claim construction; (2) the continuity chain bears on priority dates and the applicability of prior art; and (3) prosecution history estoppel arguments applicable to one patent may have implications for claims in the related patents.
The '237 Patent (Application Serial No. 14/745,210) is the earliest-filed application in the relevant chain and claims priority to Provisional Application No. 62/016,533. The '884 Patent (Application Serial No. 15/629,873) was filed as a continuation-in-part of the '237 Patent application, adding new matter relating to the blade deployment mechanism. The '105 Patent (Application Serial No. 16/508,441) was filed as a continuation-in-part of the '884 Patent application, adding further new matter relating to the integrated insufflation valve design.
The specifications of all three patents share substantial common text and figures, particularly in the sections describing the general trocar assembly structure, the seal housing, and the instrument channel. The '884 Patent specification adds detailed disclosure of the cam-follower blade deployment mechanism (Figures 8-14 of the '884 Patent), and the '105 Patent specification adds disclosure of the integrated insufflation valve and seal design (Figures 15-22 of the '105 Patent). These shared specification disclosures and distinct new-matter additions have implications for claim differentiation arguments: to the extent that Apex argues a broad construction for a claim term in one patent, it must reconcile that construction with the narrower amendments and arguments made in the prosecution of the related patents, which share the same specification language.
In addition to the three asserted patents, the broader Apex Trocar Patent Family includes eleven additional issued U.S. patents and six pending continuation applications. While a comprehensive analysis of the entire family is beyond the scope of this memorandum, we note that prosecution history arguments made in the non-asserted family members may also constitute relevant intrinsic evidence for claim construction purposes. We recommend that the team review the prosecution histories of the non-asserted family members as resources permit, particularly those that claim priority to or share specification language with the three asserted patents.
III. Prosecution History Analysis — U.S. Patent No. 9,814,237 (the '237 Patent)
A. Application Filing and Original Claims
Application Serial No. 14/745,210, which ultimately issued as the '237 Patent, was filed on June 22, 2015, by Dr. Raymond Szabo as the sole named inventor, with Apex Surgical Innovations, Inc. identified as the applicant and assignee. The application claimed priority to Provisional Application No. 62/016,533, filed June 24, 2014. The application as originally filed contained twenty (20) claims: three independent claims (Claims 1, 15, and 18) and seventeen dependent claims.
Original Independent Claim 1 as Filed. As originally filed, independent Claim 1 of the '237 Patent application recited:
1. A seal assembly for a surgical access device, comprising:
a housing defining a channel therethrough for receiving a surgical instrument;
a sealing element disposed within the housing and configured to form a seal around the surgical instrument inserted through the channel; and
a locking mechanism coupled to the housing and configured to secure the sealing element in a sealed position.
This claim was remarkably broad. It encompassed virtually any seal assembly for a surgical access device (including trocars) that had a housing, a sealing element, and any type of locking mechanism. There was no limitation on the type of sealing element (e.g., no requirement that it be elastomeric, radially compressible, or disposed in any particular orientation), no limitation on the type of housing (e.g., no requirement that it be rigid or annular), and no limitation on the specific structure of the locking mechanism. As discussed below, this broad claim was twice narrowed during prosecution.
Scope of Original Dependent Claims. The original dependent claims added various features to independent Claim 1, including: a specification that the sealing element is elastomeric (Claim 2); a recitation that the sealing element is configured to sealingly engage instruments of varying diameters (Claim 3); a description of the locking mechanism as comprising a detent feature (Claim 6); a requirement that the housing be rigid (Claim 7); and a recitation that the seal assembly further includes a blade-interaction surface (Claim 12). We note that Claims 3, 7, and 12 are among the asserted claims in this litigation.
Specification Disclosure and Relevant Figures. The specification of the '237 Patent provides detailed disclosure of the preferred embodiment, including a rigid annular housing containing a radially-compressible elastomeric sealing element disposed coaxially within the housing, with a locking mechanism employing circumferentially-spaced detent members. Figures 1 through 7 of the specification illustrate various views of the seal assembly, including cross-sectional views showing the coaxial disposition of the sealing element within the housing (Figures 2 and 3), detail views of the detent members (Figure 4), and schematic views of the locking mechanism in locked and unlocked positions (Figures 5 and 6). Importantly, while the specification discloses a specific preferred embodiment, the original claims were drafted far more broadly than the specification's detailed disclosure — a gap that the examiner exploited during prosecution.
B. First Office Action — Non-Final Rejection
The USPTO issued a non-final Office Action on March 17, 2016, approximately nine months after the filing date. The examiner, Brian T. Pellegrino of Art Unit 3771, rejected all twenty claims in the application.
Rejections under 35 U.S.C. § 102 (Anticipation). Claims 1-4 and 15-17 were rejected under 35 U.S.C. § 102(a)(1) as anticipated by U.S. Patent No. 8,323,195 to Whitfield et al. ("Whitfield"), which disclosed a trocar seal assembly having a housing, a sealing element disposed within the housing, and a snap-lock retention mechanism securing the seal in position. The examiner found that Whitfield's seal assembly anticipated the broad recitation of Claim 1 because it taught each claimed element: a housing defining a channel, a sealing element within the housing, and a locking mechanism coupled to the housing.
Rejections under 35 U.S.C. § 103 (Obviousness). Claims 5-14 and 18-20 were rejected under 35 U.S.C. § 103 as obvious over Whitfield in combination with U.S. Patent No. 7,931,614 to Conlon ("Conlon") and U.S. Patent Application Publication No. 2012/0253340 to Brock et al. ("Brock"). The examiner found that Conlon disclosed a trocar seal with a blade-interaction surface and that Brock disclosed a trocar housing with detent features, and that it would have been obvious to combine these features with the Whitfield seal assembly to arrive at the claimed inventions.
Key Teachings of Cited Prior Art. The Whitfield reference disclosed a locking seal assembly for a surgical trocar in which an elastomeric seal was retained within a housing by an axially-acting snap-lock mechanism. The seal in Whitfield was compressed axially — that is, along the longitudinal axis of the trocar — rather than radially. The Conlon reference disclosed a trocar assembly with a blade-interaction surface on the seal component that facilitated safe blade retraction upon tissue penetration. The Brock reference disclosed a trocar housing with detent features for securing internal components.
Examiner's Characterization. The examiner characterized the original claims as broadly reading on prior art seal configurations, noting that the claim language did not specify any particular compression mode, housing geometry, or sealing element orientation that would distinguish the claimed invention from the cited prior art. This characterization effectively invited the applicant to narrow the claims to the specific embodiment disclosed in the specification.
C. First Amendment and Applicant's Response
On September 19, 2016, Apex's prosecution counsel (Matthew R. Hagan of Whitmore & Hagan LLP, Washington, DC) filed a response to the non-final Office Action, including amendments to several claims and arguments traversing the rejections.
Critical Narrowing Amendment to Independent Claim 1. The amendment rewrote independent Claim 1 to add a specific structural limitation not present in the original claims. As amended, Claim 1 recited:
1. A seal assembly for a surgical access device, comprising:
a rigid annular housing defining a channel therethrough for receiving a surgical instrument;
a radially-compressible elastomeric sealing element disposed coaxially within the rigid annular housing and configured to form a seal around the surgical instrument inserted through the channel; and
a locking mechanism coupled to the rigid annular housing and configured to secure the radially-compressible elastomeric sealing element in a sealed position.
This amendment added three significant limitations: (1) the housing was now required to be "rigid" and "annular"; (2) the sealing element was now required to be "radially-compressible" and "elastomeric"; and (3) the sealing element was required to be "disposed coaxially within" the rigid annular housing. None of these specific structural requirements appeared in the original claim language.
Arguments Made by Applicant to Distinguish Prior Art. In the accompanying remarks, Apex's prosecution counsel argued that the amended claims distinguished the cited prior art on two principal grounds:
First, counsel argued that Whitfield disclosed only an axially-compressed seal — one compressed along the longitudinal axis of the trocar — and did not teach or suggest a radially-compressible sealing element. Counsel stated: "Unlike the axially-compressed seal of Whitfield, the claimed radially-compressible elastomeric sealing element is compressed in a direction perpendicular to the instrument axis, providing a fundamentally different sealing mechanism with superior conformability to instruments of varying diameters." (September 19, 2016 Amendment at 8.)
Second, counsel argued that the "coaxial disposition within a rigid annular housing" was a distinguishing structural feature not present in the prior art. Counsel stated: "The prior art of record does not disclose or suggest a sealing element that is coaxially disposed within a rigid annular housing. Whitfield's seal is retained by a snap-lock at one axial end of the housing, not disposed coaxially within an annular structure." (Id. at 9.)
Amendments to Asserted Dependent Claims 3, 7, and 12. Dependent Claim 3 was amended to add the limitation "wherein the radially-compressible elastomeric sealing element is configured to sealingly engage surgical instruments having diameters ranging from 3 mm to 15 mm through radial compression of the sealing element against the surgical instrument." Dependent Claim 7 was amended to further specify that "the rigid annular housing comprises an inner annular surface defining the channel and an outer annular surface, wherein the locking mechanism is disposed on the outer annular surface." Dependent Claim 12 was amended to recite "a blade-interaction surface formed on the radially-compressible elastomeric sealing element, the blade-interaction surface configured to sealingly engage a retractable blade of the surgical access device during blade retraction." Each of these amendments further narrowed the asserted dependent claims by tying them more closely to the specific structural features of the preferred embodiment.
Estoppel Implications. The narrowing amendment to Claim 1 and the accompanying arguments have significant prosecution history estoppel implications. Under the framework established by the Supreme Court in Festo Corp. v. Fenmore & Co., 535 U.S. 722 (2002), when a patentee narrows a claim in response to a prior art rejection, there is a presumption that the patentee surrendered the territory between the original claim and the amended claim, and the patentee cannot recapture that territory through the doctrine of equivalents. Here, the amendment to Claim 1 surrendered scope covering: (a) seal assemblies using axially-compressed seals (as opposed to radially-compressible seals); (b) seal assemblies in which the sealing element is not elastomeric; (c) seal assemblies in which the sealing element is not disposed coaxially within a rigid annular housing; and (d) seal assemblies in which the housing is not rigid or not annular.
In addition to amendment-based estoppel, the applicant's remarks create argument-based estoppel. By distinguishing the invention from the prior art on the basis that the claimed sealing element is radially-compressible rather than axially-compressed, and that it is coaxially disposed within a rigid annular housing, Apex limited its ability to assert infringement under the doctrine of equivalents against structures employing different compression modes or non-coaxial configurations. See Southwall Techs., Inc. v. Cardinal IG Co., 54 F.3d 1570, 1576 (Fed. Cir. 1995) (argument-based estoppel arises when the patentee makes clear and unmistakable arguments to the USPTO that limit the scope of the claims).
D. Second Office Action — Final Rejection
On February 10, 2017, the examiner issued a final rejection of the amended claims. The final rejection maintained the obviousness rejection under 35 U.S.C. § 103 but was based on an expanded combination of prior art references.
Additional Prior Art References Cited. In addition to the previously cited Whitfield, Conlon, and Brock references, the examiner cited U.S. Patent No. 8,858,478 to Greenberg ("Greenberg"), which disclosed a trocar seal assembly with an elastomeric seal element compressed radially within an annular housing. The examiner argued that Greenberg, in combination with Whitfield and Conlon, rendered the amended claims obvious because Greenberg taught the "radially-compressible" and "coaxial" disposition elements that the applicant had argued were absent from the prior art.
Examiner's Statements. The examiner addressed the scope of the "radially-compressible" limitation, noting that Greenberg's seal element was compressed radially during instrument insertion and that the element was disposed within an annular retaining ring. The examiner acknowledged that Greenberg's annular retaining ring was not specifically described as "rigid" in the reference but argued that the use of a rigid housing would have been an obvious design choice. The examiner also addressed the "coaxially" limitation, finding that Greenberg's seal was coaxially arranged within the retaining ring and thus met this element. The examiner concluded that the combination of Whitfield (for the general trocar seal assembly), Greenberg (for the radially-compressible elastomeric element coaxially disposed in an annular housing), and Conlon (for the blade-interaction features) rendered the claimed invention obvious.
E. After-Final Response and Request for Continued Examination (RCE)
On June 14, 2017, Apex's prosecution counsel filed a Request for Continued Examination ("RCE") under 37 C.F.R. § 1.114, accompanied by further amendments to the claims and arguments traversing the final rejection.
Additional Narrowing of Claim 1. The RCE included a second round of amendments to independent Claim 1, further specifying the structure of the locking mechanism. As amended in the RCE, Claim 1 recited:
1. A seal assembly for a surgical access device, comprising:
a rigid annular housing defining a channel therethrough for receiving a surgical instrument;
a radially-compressible elastomeric sealing element disposed coaxially within the rigid annular housing and configured to form a seal around the surgical instrument inserted through the channel; and
a locking mechanism coupled to the rigid annular housing and configured to secure the radially-compressible elastomeric sealing element in a sealed position, wherein the locking mechanism comprises a plurality of circumferentially-spaced detent members extending radially inward from the rigid annular housing and engaging corresponding detent recesses formed on an outer surface of the radially-compressible elastomeric sealing element.
This amendment added a detailed structural limitation defining the locking mechanism as comprising "a plurality of circumferentially-spaced detent members extending radially inward from the rigid annular housing and engaging corresponding detent recesses formed on an outer surface of the radially-compressible elastomeric sealing element." This language tracks the specific embodiment disclosed in Figures 4 and 5 of the specification and narrows the claim from any locking mechanism to a specific detent-based locking arrangement.
Arguments Distinguishing the Prior Art. In the accompanying remarks, counsel argued that none of the cited references, alone or in combination, disclosed or suggested the specific detent-member-and-recess locking arrangement recited in the amended claim. Counsel characterized Greenberg's retaining ring as a "simple interference fit" rather than a "plurality of circumferentially-spaced detent members engaging corresponding detent recesses," and argued that Whitfield's snap-lock mechanism operated axially rather than radially and did not employ circumferentially-spaced detent members. Counsel further argued that there was no motivation in the prior art to combine the specific detent-member locking arrangement with the radially-compressible sealing element.
Estoppel Implications. This second round of amendments further narrows the claim scope and creates additional amendment-based estoppel. The addition of the specific detent-member-and-recess limitation surrendered scope covering locking mechanisms that do not employ a plurality of circumferentially-spaced detent members engaging corresponding detent recesses. Moreover, the arguments made regarding the specific structural arrangement of the detent members create argument-based estoppel, as the applicant distinguished the invention from prior art locking mechanisms (interference fits, snap-locks, and axially-acting retention features) by emphasizing the unique radially-inward-extending, circumferentially-spaced detent arrangement.
F. Examiner Interview
On August 3, 2017, an examiner interview was conducted between Examiner Pellegrino and Mr. Hagan on behalf of Apex. The interview summary, filed on August 7, 2017, records the following key points:
The examiner indicated that the amendments filed with the RCE had addressed his prior art concerns and that the specific combination of the radially-compressible elastomeric sealing element, coaxial disposition within a rigid annular housing, and the detent-member-and-recess locking mechanism was not disclosed or suggested by the cited prior art. The examiner proposed minor clarifying language for dependent Claims 7 and 12 to more clearly define the relationship between the outer annular surface of the housing and the blade-interaction surface. The applicant agreed to incorporate the examiner's proposed language.
Specifically, the examiner proposed that Claim 7 be amended to recite "wherein the outer annular surface of the rigid annular housing includes a seating groove configured to receive a complementary protrusion of a trocar cannula," and that Claim 12 be amended to recite "wherein the blade-interaction surface is integrally formed with the radially-compressible elastomeric sealing element." The applicant agreed to these proposed amendments, and they were incorporated into supplemental amendments filed on August 10, 2017.
The examiner interview summary is part of the prosecution history record and constitutes intrinsic evidence for claim construction purposes. The examiner's characterization of the distinguishing features of the invention — the specific combination of the radially-compressible element, coaxial disposition, and detent-member locking — further supports a narrow construction of the asserted claims.
G. Notice of Allowance
The examiner issued a Notice of Allowance on August 29, 2017. The examiner provided a brief statement of reasons for allowance, noting that "the prior art of record does not teach or suggest, alone or in combination, a seal assembly for a surgical access device comprising a radially-compressible elastomeric sealing element disposed coaxially within a rigid annular housing with a locking mechanism comprising a plurality of circumferentially-spaced detent members extending radially inward from the rigid annular housing and engaging corresponding detent recesses formed on an outer surface of the sealing element, in combination with the remaining claim limitations."
The patent issued on November 14, 2017, with the final allowed claim language as amended through the prosecution process described above.
Final Allowed Claim Language for Asserted Claims:
Claim 1: A seal assembly for a surgical access device, comprising: a rigid annular housing defining a channel therethrough for receiving a surgical instrument; a radially-compressible elastomeric sealing element disposed coaxially within the rigid annular housing and configured to form a seal around the surgical instrument inserted through the channel; and a locking mechanism coupled to the rigid annular housing and configured to secure the radially-compressible elastomeric sealing element in a sealed position, wherein the locking mechanism comprises a plurality of circumferentially-spaced detent members extending radially inward from the rigid annular housing and engaging corresponding detent recesses formed on an outer surface of the radially-compressible elastomeric sealing element.
Claim 3: The seal assembly of claim 1, wherein the radially-compressible elastomeric sealing element is configured to sealingly engage surgical instruments having diameters ranging from 3 mm to 15 mm through radial compression of the sealing element against the surgical instrument.
Claim 7: The seal assembly of claim 1, wherein the rigid annular housing comprises an inner annular surface defining the channel and an outer annular surface, wherein the locking mechanism is disposed on the outer annular surface, and wherein the outer annular surface includes a seating groove configured to receive a complementary protrusion of a trocar cannula.
Claim 12: The seal assembly of claim 1, further comprising a blade-interaction surface integrally formed with the radially-compressible elastomeric sealing element, the blade-interaction surface configured to sealingly engage a retractable blade of the surgical access device during blade retraction.
H. Summary of Estoppel Arguments for the '237 Patent
The prosecution history of the '237 Patent provides the following estoppel arguments for Solstice's defense:
Amendment-Based Estoppel (*Festo*). Independent Claim 1 was narrowed in at least two rounds of substantive amendments in response to prior art rejections. The first amendment (September 19, 2016) added the requirements of a "rigid annular housing," a "radially-compressible elastomeric sealing element," and "coaxial" disposition. The second amendment (June 14, 2017, filed with RCE) added the specific "plurality of circumferentially-spaced detent members" locking mechanism. Under Festo, there is a presumption that Apex surrendered the territory between the original claim and the amended claim — i.e., equivalents in the territory of seal assemblies that do not meet the specific structural limitations added during prosecution. Apex bears the burden of rebutting this presumption, which it can do only by showing that (a) the equivalent was unforeseeable at the time of the amendment, (b) the rationale for the amendment bears no more than a tangential relation to the equivalent, or (c) there is some other reason the patentee could not reasonably have been expected to have drafted a claim covering the equivalent. Given that the amendments were made specifically to distinguish prior art disclosing alternative seal structures, it will be difficult for Apex to satisfy any of these exceptions for equivalents that fall within the surrendered territory.
Argument-Based Estoppel. The applicant's representations that the invention is distinguished by (1) a radially-compressible (not axially-compressed) sealing element and (2) coaxial disposition within a rigid annular housing limit Apex's ability to assert infringement under the doctrine of equivalents against structures using different compression modes (e.g., axial compression) or non-coaxial configurations. The applicant's characterization of the prior art as limited to "axially-compressed seals" and the invention as employing a "fundamentally different sealing mechanism" based on radial compression creates a clear and unmistakable prosecution history record that forecloses expansion back to axially-compressed designs.
Relevance to Accused Products. These estoppel arguments are directly relevant to Solstice's defense of the PrecisionEdge™ PE-5000 and PE-12000 Series. If the accused products employ seal configurations that differ from the narrowed claim language — for example, if they use an axially-compressed seal, a non-coaxial seal arrangement, or a locking mechanism that does not employ circumferentially-spaced detent members — prosecution history estoppel may preclude Apex from reaching them under the doctrine of equivalents. Preliminary review of the PE-5000 and PE-12000 product designs suggests that the sealing mechanisms in these products differ in certain respects from the specific structural configuration recited in the allowed claims, but a detailed comparison is deferred to the non-infringement claim charts and expert analysis.
IV. Prosecution History Analysis — U.S. Patent No. 10,271,884 (the '884 Patent)
A. Application Filing and Original Claims
Application Serial No. 15/629,873, which ultimately issued as the '884 Patent, was filed on June 21, 2017, as a continuation-in-part of Application Serial No. 14/745,210 (the application that issued as the '237 Patent). The continuation-in-part added new matter to the specification relating to the retractable blade deployment mechanism, including detailed descriptions of a cam-follower linkage, blade carrier geometry, and spring-biased return mechanisms (Figures 8 through 14). The application as originally filed contained twenty-two (22) claims: four independent claims (Claims 1, 10, 16, and 20) and eighteen dependent claims. Dr. Raymond Szabo was again the sole named inventor, and Apex Surgical Innovations, Inc. was identified as the applicant and assignee.
Original Independent Claim 1 as Filed. As originally filed, independent Claim 1 of the '884 Patent application recited:
1. A retractable blade deployment mechanism for a trocar system, comprising:
a blade carrier supporting a surgical blade;
an actuator configured for axial displacement by a user; and
a linkage operatively connecting the actuator to the blade carrier, wherein axial displacement of the actuator causes deployment of the surgical blade from a retracted position to an extended position.
This original claim was broadly drafted to cover any retractable blade deployment mechanism in which axial displacement of an actuator causes blade deployment through any type of "linkage." There was no limitation on the type of linkage (e.g., no requirement for a cam-follower mechanism), no limitation on the type of motion imparted to the blade carrier (e.g., no requirement for rotational displacement), and no specification of the blade retraction mechanism.
Scope of Original Dependent Claims. The original dependent claims added various features, including: a spring-biased return to the retracted position (Claim 2); a specification that the linkage comprises a cam surface (Claim 4); a recitation of a blade guard (Claim 5); angular displacement parameters for the blade carrier (Claim 9); and specific spring constant ranges for the return spring (Claim 14). Notably, the dependent claims disclosed progressively more specific features of the preferred embodiment, but the independent claim remained broad. We note that Claims 1, 2, 5, 9, and 14 are among the asserted claims in this litigation.
B. First Office Action — Restriction Requirement
The examiner, Patricia L. Chen of Art Unit 3771, issued a restriction requirement on January 22, 2018, identifying three distinct inventions within the application:
Group I: Claims 1-9 — directed to a retractable blade deployment mechanism with a spring-biased return to the retracted position.
Group II: Claims 10-15 — directed to a retractable blade deployment mechanism with a pneumatic return to the retracted position.
Group III: Claims 16-22 — directed to a retractable blade deployment mechanism with a ratchet-lock mechanism for maintaining the blade in the extended position.
The examiner found that these groups represented distinct inventions because they recited mutually exclusive blade return and retention mechanisms that would require different search strategies and raise different patentability issues.
Applicant's Election. On March 5, 2018, Apex elected prosecution of Group I (Claims 1-9) — the retractable blade mechanism with spring-biased return — without traverse. Claims 10-22 were withdrawn from prosecution. The applicant subsequently added new dependent Claims 23-30, of which Claims 23-28 were renumbered during prosecution and ultimately issued as Claims 10-15 of the patent (including asserted Claim 14).
Implications. The restriction requirement and the applicant's election have two notable implications. First, the non-elected claims directed to pneumatic return mechanisms (Group II) and ratchet-lock mechanisms (Group III) were withdrawn and not prosecuted, meaning that Apex abandoned the opportunity to obtain patent protection for those alternative blade deployment configurations in this application. While Apex could have (and may have) pursued those claims in divisional applications, the withdrawal of these claims from the '884 Patent prosecution may support an argument that the '884 Patent is limited to the spring-biased return mechanism. Second, the restriction requirement itself confirms the examiner's view that the different deployment mechanism configurations represented distinct inventions, supporting Solstice's position that the claims should be construed narrowly to cover only the elected configuration.
C. Second Office Action — Non-Final Rejection on Elected Claims
On June 8, 2018, the examiner issued a non-final Office Action rejecting the elected claims (Claims 1-9 and newly added Claims 23-30) under 35 U.S.C. § 102 and § 103.
Rejection under 35 U.S.C. § 102 (Anticipation). Claims 1-3 were rejected under § 102(a)(1) as anticipated by U.S. Patent No. 7,537,564 to Hart ("Hart"). The examiner found that Hart disclosed a trocar assembly with a retractable blade, an actuator movable along the longitudinal axis of the trocar, and a linkage connecting the actuator to a blade carrier. Hart's blade deployment mechanism was a direct-acting mechanism in which axial movement of the actuator caused direct axial deployment of the blade without any motion conversion. The examiner found that Hart's mechanism met each element of original Claim 1.
Rejection under 35 U.S.C. § 103 (Obviousness). Claims 4-9 and 23-30 were rejected under § 103 as obvious over Hart in combination with U.S. Patent No. 8,197,472 to Kimura et al. ("Kimura") and U.S. Patent Application Publication No. 2013/0267963 to Palanker ("Palanker"). The examiner found that Kimura disclosed a cam-follower mechanism in the context of a medical device deployment system (though not specifically a trocar) and that Palanker disclosed spring-return mechanisms for retractable surgical blades. The examiner concluded that it would have been obvious to combine Hart's trocar blade deployment mechanism with Kimura's cam-follower linkage and Palanker's spring-return mechanism to arrive at the claimed invention.
Examiner's Characterization. The examiner specifically noted that Hart's disclosure of a spring-loaded retractable blade in a trocar assembly anticipated the broad recitation of Claim 1 because the original claim did not require any specific type of linkage or any particular mode of motion conversion. The examiner observed that "the claim as currently written reads on any mechanism that operatively connects an axially-displaced actuator to a blade carrier to cause blade deployment, which is broadly met by the direct-acting axial linkage of Hart." (June 8, 2018 Office Action at 5.)
D. First Amendment — Key Narrowing Amendment
On October 8, 2018, Apex's prosecution counsel filed a response to the non-final Office Action, including substantive amendments to the claims and detailed arguments traversing the rejections.
Critical Amendment to Claim 1. The amendment rewrote independent Claim 1 to require a specific type of linkage and a specific type of motion conversion. As amended, Claim 1 recited:
1. A retractable blade deployment mechanism for a trocar system, comprising:
a blade carrier supporting a surgical blade;
an actuator configured for axial displacement by a user; and
a cam-follower linkage operatively connecting the actuator to the blade carrier, wherein axial displacement of the actuator causes rotational displacement of the blade carrier through the cam-follower linkage, thereby deploying the surgical blade from a retracted position to an extended position along a deployment arc.
This amendment made three critical changes: (1) it changed "a linkage" to "a cam-follower linkage," thereby limiting the claim to a specific type of mechanical linkage; (2) it added the requirement that the cam-follower linkage cause "rotational displacement" of the blade carrier, specifying the mode of motion conversion; and (3) it added the requirement that the blade deploy "along a deployment arc," a direct consequence of the rotational displacement. These amendments fundamentally changed the scope of the claim from covering any axial-actuator-based blade deployment mechanism to one specifically requiring a cam-follower linkage that converts axial motion to rotational motion resulting in arc-path blade deployment.
Arguments Made by Applicant. The accompanying remarks contained extensive arguments distinguishing the amended claims from the cited prior art:
First, counsel argued that Hart disclosed only a "direct axial" blade deployment mechanism — one in which axial displacement of the actuator caused direct axial displacement of the blade without any motion conversion — and did not disclose or suggest a cam-follower linkage that converts axial motion to rotational motion. Counsel stated: "Hart's blade moves in a straight line along the trocar axis. There is no cam surface, no follower, and no conversion of axial motion to rotational motion. The present invention's cam-follower linkage operates on a fundamentally different mechanical principle." (October 8, 2018 Amendment at 7.)
Second, counsel characterized the cam-follower linkage as providing a "controlled and predictable blade deployment arc" that was not achieved by prior art direct-acting deployment mechanisms. Counsel argued: "The use of a cam-follower linkage to convert axial displacement to rotational displacement of the blade carrier provides a precisely controlled blade deployment arc, ensuring that the blade follows a predictable curved path during deployment. This is in stark contrast to the linear deployment of Hart, which provides no arc control." (Id. at 8.)
Third, counsel addressed the Kimura reference, arguing that Kimura's cam-follower mechanism was disclosed in the context of a non-trocar medical device and that there was no motivation to combine Kimura's mechanism with Hart's trocar because the mechanical requirements and design constraints of trocar blade deployment are fundamentally different from those of the device disclosed in Kimura. (Id. at 9-10.)
Amendments to Asserted Dependent Claims 2, 5, 9, and 14. Dependent Claim 2 was amended to specify that the spring-biased return mechanism is "configured to return the blade carrier to the retracted position upon release of the actuator by biasing the cam-follower linkage to an initial position." Dependent Claim 5 was amended to add that "the blade guard is configured to retract concurrently with rotational deployment of the blade carrier through the cam-follower linkage." Dependent Claim 9 was amended to require "an angular displacement range of the blade carrier between 45 degrees and 135 degrees during deployment from the retracted position to the extended position through the cam-follower linkage." Dependent Claim 14 was amended to require "a return spring having a spring constant in the range of 0.5 N/mm to 3.0 N/mm."
Estoppel Implications. The amendment to Claim 1 creates strong amendment-based estoppel. The change from "a linkage" to "a cam-follower linkage" and the addition of the "rotational displacement" and "deployment arc" limitations surrendered the entire territory of blade deployment mechanisms that do not employ a cam-follower linkage converting axial displacement to rotational displacement. Under Festo, the presumption of surrender applies, and Apex is presumptively estopped from asserting that a non-cam-follower mechanism — or a mechanism that does not convert axial motion to rotational motion — infringes under the doctrine of equivalents.
The arguments made by counsel further reinforce this estoppel. By repeatedly characterizing the prior art as limited to "direct axial" blade deployment and the claimed invention as uniquely employing "cam-follower conversion" producing a "controlled and predictable blade deployment arc," the applicant created a clear prosecution history record that forecloses expansion back to direct-axial deployment mechanisms. These arguments constitute argument-based estoppel that operates independently of the amendment-based estoppel.
E. Third Office Action — Final Rejection
On February 1, 2019, the examiner issued a final rejection maintaining the obviousness rejection under 35 U.S.C. § 103 based on the combination of Hart, Kimura, and Palanker.
Examiner's Position. The examiner argued that the amendment to require a cam-follower linkage did not overcome the obviousness rejection because cam-follower linkages were well-known mechanical elements used extensively in medical device design and other fields. The examiner stated: "Cam-follower linkages for converting linear motion to rotational motion are well-known in the mechanical arts. Kimura specifically discloses a cam-follower mechanism in a medical device context. The application of this known mechanism to Hart's trocar blade deployment system would have been a matter of routine engineering design choice." (February 1, 2019 Final Rejection at 6.)
Applicant's After-Final Response. On April 15, 2019, the applicant filed a response after final, arguing that the examiner's characterization of the cam-follower linkage as a "routine engineering design choice" was unsupported by the evidence and contrary to the specific mechanical requirements of trocar blade deployment. The response was accompanied by a declaration under 37 C.F.R. § 1.132 by Dr. Raymond Szabo.
F. Szabo Declaration (37 C.F.R. § 1.132)
The declaration by Dr. Raymond Szabo, dated April 10, 2019, was submitted in support of the after-final response and contained the following key statements:
Paragraphs 5-8: Dr. Szabo stated that he is the sole inventor of the claimed retractable blade deployment mechanism and that he has over 20 years of experience in the design and development of minimally invasive surgical instruments, including trocar systems. He described the specific design challenges associated with blade deployment in trocars, including the need for precise control of the blade deployment arc to ensure safe tissue penetration without excessive tissue damage.
Paragraphs 9-12: Dr. Szabo asserted that the specific cam-follower geometry claimed in the '884 Patent application was not taught or suggested by the prior art. He stated that Hart's direct-axial deployment mechanism provided no arc control and resulted in unpredictable blade exposure, and that Kimura's cam-follower mechanism was designed for a fundamentally different purpose and lacked the geometric parameters necessary for safe trocar blade deployment.
Paragraphs 13-16: Dr. Szabo asserted that the combination of the specific cam-follower linkage with a spring-biased return mechanism in the trocar context achieved unexpected results in blade deployment precision, specifically: (a) a reduction in blade over-deployment of approximately 40% compared to direct-axial mechanisms; (b) a more consistent blade retraction profile reducing the risk of tissue entrapment; and (c) improved tactile feedback to the surgeon during tissue penetration.
Paragraphs 17-20: Dr. Szabo described the commercial success of Apex's trocar products embodying the claimed invention, stating that Apex's TrocarGuard™ product line incorporating the cam-follower blade deployment mechanism had achieved U.S. sales of over $120 million since launch in 2016, capturing approximately 18% of the U.S. trocar market. He attributed this commercial success to the specific cam-follower mechanism and the resulting blade deployment precision and safety.
Significance for Invalidity Defense. The Szabo declaration is significant for Solstice's defense in several respects. First, Dr. Szabo's statements regarding the specific cam-follower geometry and its relationship to blade deployment precision and safety may be used to impeach Dr. Szabo at deposition or trial if his testimony is inconsistent with the declaration. Second, the "unexpected results" characterization (40% reduction in over-deployment, improved retraction profile, improved tactile feedback) sets a specific standard of performance that Solstice can use to argue that any differences between the accused PrecisionEdge™ products and the claimed invention are material — if the PrecisionEdge™ products achieve comparable results through a different mechanism, that undermines the assertion that the specific cam-follower geometry was necessary to achieve the claimed benefits. Third, the commercial success evidence cited in the declaration (sales of $120 million, 18% market share) may be subject to challenge on the basis that the commercial success is attributable to factors other than the patented cam-follower mechanism (e.g., brand recognition, sales force strength, hospital purchasing contracts).
Significance for Estoppel. The declaration reinforced the narrowness of the claimed invention by emphasizing the specific cam-follower geometry as the source of the claimed benefits. Dr. Szabo's repeated characterization of the invention in terms of the cam-follower mechanism's specific advantages further narrows the scope of equivalents available to Apex, as the declaration provides additional intrinsic evidence that the patentee considered the specific cam-follower geometry to be the core of the invention.
G. RCE and Further Amendments
On May 20, 2019, the applicant filed a Request for Continued Examination under 37 C.F.R. § 1.114, accompanied by the Szabo declaration (which had been filed after-final) and additional amendments to the dependent claims.
Amendments to Asserted Dependent Claims. Claim 9 was further amended to require "an angular displacement range of the blade carrier of between 60 degrees and 120 degrees during deployment from the retracted position to the extended position through the cam-follower linkage." This narrowed the previously recited range of 45-135 degrees to 60-120 degrees, further restricting the scope of the claim. Claim 14 was further amended to require "a return spring having a spring constant in the range of 0.8 N/mm to 2.5 N/mm," narrowing the previously recited range of 0.5-3.0 N/mm.
These numerical limitations further constrain the scope of the asserted dependent claims and provide additional estoppel arguments if the accused products operate outside the claimed ranges. The narrowing of the angular displacement and spring constant ranges may be particularly relevant to Solstice's non-infringement defense if the PrecisionEdge™ products employ different deployment angles or spring constants.
H. Examiner Interview and Allowance
An examiner interview was conducted on June 12, 2019, between Examiner Chen and Mr. Hagan. The interview summary records that the examiner indicated willingness to allow the claims with the cam-follower linkage limitations and the specific geometry and spring-return specifications, in view of the Szabo declaration and the applicant's arguments distinguishing the prior art. The examiner noted that the combination of the specific cam-follower geometry with the spring-biased return mechanism in the trocar blade deployment context was not taught or suggested by the cited prior art and that the Szabo declaration provided sufficient evidence of unexpected results to overcome the obviousness rejection.
A Notice of Allowance was issued on June 28, 2019, and the patent issued on April 30, 2019 (the Notice of Allowance having been expedited under the USPTO's accelerated examination procedures, with the issue date reflecting an earlier mailing of the issue notification). The examiner's reasons for allowance stated that "the combination of a cam-follower linkage operatively connecting an actuator to a blade carrier, wherein axial displacement of the actuator causes rotational displacement of the blade carrier through the cam-follower linkage to deploy a surgical blade along a deployment arc, in combination with a spring-biased return, as recited in independent Claim 1 and its dependent claims, is not taught or suggested by the prior art of record."
Final Allowed Claim Language for Asserted Claims:
Claim 1: A retractable blade deployment mechanism for a trocar system, comprising: a blade carrier supporting a surgical blade; an actuator configured for axial displacement by a user; and a cam-follower linkage operatively connecting the actuator to the blade carrier, wherein axial displacement of the actuator causes rotational displacement of the blade carrier through the cam-follower linkage, thereby deploying the surgical blade from a retracted position to an extended position along a deployment arc.
Claim 2: The retractable blade deployment mechanism of claim 1, further comprising a spring-biased return mechanism configured to return the blade carrier to the retracted position upon release of the actuator by biasing the cam-follower linkage to an initial position.
Claim 5: The retractable blade deployment mechanism of claim 2, further comprising a blade guard configured to retract concurrently with rotational deployment of the blade carrier through the cam-follower linkage.
Claim 9: The retractable blade deployment mechanism of claim 1, wherein the blade carrier undergoes an angular displacement in the range of 60 degrees to 120 degrees during deployment from the retracted position to the extended position through the cam-follower linkage.
Claim 14: The retractable blade deployment mechanism of claim 2, wherein the spring-biased return mechanism comprises a return spring having a spring constant in the range of 0.8 N/mm to 2.5 N/mm.
I. Summary of Estoppel Arguments for the '884 Patent
The prosecution history of the '884 Patent provides the following estoppel arguments for Solstice's defense:
Amendment-Based Estoppel. The narrowing of Claim 1 from a generic "linkage" causing blade deployment through axial displacement to a specific "cam-follower linkage" causing "rotational displacement" along a "deployment arc" creates strong amendment-based estoppel under Festo. The presumption of surrender applies to the entire territory of blade deployment mechanisms that do not employ a cam-follower linkage converting axial displacement to rotational displacement. This includes, without limitation, direct-axial deployment mechanisms, gear-train mechanisms, lever-arm mechanisms, and any other linkage type that does not employ a cam surface and follower element to convert axial motion to rotational motion. The additional narrowing of dependent Claims 9 and 14 to sp

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MATTER NO.: 10294.0017

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