Contract analysis

1. INTRODUCTION AND PURPOSE Calderwood & Harkness LLP ("C&H" or the "Firm") is pleased to present this draft engagement letter setting forth the proposed terms under which C&H would represent Penterra Pharmaceuticals Corp. ("PPC" or the "Company") in connection with the defense of the Internal Revenue Service ("IRS") Large Business & International Division ("LB&I") examination of PPC's transfer pricing methodology fo

2. THE CLIENT The client for this engagement is Penterra Pharmaceuticals Corp., Employer Identification Number ("EIN") 22-3741856. C&H will not separately represent any PPC subsidiary, affiliate, or related entity in connection with this Examination, including without limitation: (a) Penterra Biopharma International DAC ("PBI"), a Designated Activity Company organized under the laws of Ireland, with its registered of

3. SCOPE OF ENGAGEMENT 3.1 Overview of the Matter The IRS has opened a multi-year examination challenging the transfer pricing methodology employed by PPC in connection with its Irish intellectual-property-holding structure involving PBI. The Examination covers PPC's U.S. federal income tax returns (Forms 1120) for tax years ending December 31, 2017, December 31, 2018, December 31, 2019, and December 31, 2020 (collec

4. ENGAGEMENT TEAM AND STAFFING PLAN 4.1 Team Members C&H has assembled a team of experienced tax controversy professionals to represent PPC in the Examination. The core engagement team will consist of the following individuals: Leonard Cross — Responsible Partner, Tax Department Mr. Cross is a partner in C&H's Tax Department based in the Firm's Philadelphia office at 1735 Market Street, Suite 3100, Philadelphia, PA

5. FEE ARRANGEMENTS 5.1 Hourly Billing Rates (2022) C&H will bill PPC for legal services rendered in connection with this engagement on an hourly basis at the following 2022 standard rates for the core engagement team: The foregoing rates are subject to annual adjustment, which is typically effective as of January 1 of each calendar year. C&H will notify PPC in advance of any rate increases. Given the anticipated dur

6. RETENTION OF EXPERT CONSULTANTS As discussed in Sections 3.2 and 4.2 above, C&H proposes to retain Whitmore Valuation Group LLC ("WVG") under a Kovel arrangement to perform independent economic analyses in support of C&H's legal advice to PPC. The Kovel arrangement is designed to bring WVG's economic analysis within the scope of the attorney-client privilege by having WVG perform its services at the direction of C

7. COORDINATION WITH OTHER ADVISORS 7.1 Crestfield & Associates LLP PPC's independent auditor and preparer of PPC's consolidated U.S. federal income tax returns (Forms 1120) for the Tax Years at Issue is Crestfield & Associates LLP ("Crestfield"), located at 1200 Avenue of the Americas, New York, NY 10036. The engagement partner for PPC's audit is Martin Ogilvy, CPA, and the transfer pricing partner responsible for P

8. PRIVILEGE AND CONFIDENTIALITY 8.1 Attorney-Client Privilege All communications between C&H and PPC in connection with this engagement are intended to be protected by the attorney-client privilege. This includes written and oral communications, memoranda, emails, analyses, and other materials prepared by C&H in the course of providing legal advice to PPC. To preserve the privilege, PPC should take care to limit the

9. CONFLICTS OF INTEREST C&H has conducted a preliminary conflicts check in accordance with the Firm's conflicts policies and the applicable Rules of Professional Conduct, and has not identified any conflict of interest that would preclude the Firm's representation of PPC in connection with this engagement. Specifically, C&H does not currently represent and has not recently represented any of the following parties in

10. LIMITATIONS ON SCOPE This engagement is limited exclusively to the defense of the IRS transfer pricing examination described herein for Tax Years 2017, 2018, 2019, and 2020. Except as expressly set forth in Section 3 above, this engagement does not extend to the following matters: (a) U.S. Tax Court Litigation. Representation of PPC in any proceeding before the United States Tax Court, including the filing of a p

11. TERM AND TERMINATION This engagement will commence upon execution of this engagement letter by both C&H and PPC and will continue until the earlier of (a) the completion of the Matter, which is anticipated to be through the resolution of the Examination at the IRS Appeals level (whether by settlement, full concession, or issuance of a statutory notice of deficiency), or (b) the termination of the engagement by ei

12. GOVERNING LAW AND DISPUTE RESOLUTION This engagement letter shall be governed by and construed in accordance with the laws of the State of New York, without regard to its conflict-of-laws principles. In the event of any dispute, claim, or controversy arising out of or relating to this engagement letter or the services provided hereunder, including any dispute regarding the amount or reasonableness of fees or expe

13. ACCEPTANCE AND EXECUTION This draft engagement letter is circulated for discussion purposes only and does not constitute a binding agreement between C&H and PPC. Upon agreement on the terms set forth herein, a final version of this engagement letter will be prepared and presented for execution by authorized representatives of both parties. The final engagement letter will require the following signatures: (a) On