Contract analysis

I. Purpose and Summary This memorandum documents the results of the conflicts clearance process conducted in connection with Calderwood & Harkness LLP's ("C&H" or the "Firm") proposed representation of Northgate Telecommunications PLC ("Northgate" or "NTP") as acquirer's counsel in its proposed $750,000,000 all-cash forward merger acquisition of Cascadia Fiber Networks, Inc. ("Cascadia" or "CFN"). The memorandum has

II. Engagement Background The following summarizes the material facts concerning the proposed engagement and the underlying transaction, based on information provided by the client and gathered through the engagement intake process. Client. The prospective client is Northgate Telecommunications PLC, a public limited company organized and existing under the laws of England and Wales, with its principal executive offic

III. Parties and Entities Searched The following is a comprehensive list of all parties, entities, and individuals included in the conflicts search. Each party, entity, and individual was searched using all known names, trade names, short names, and commonly used abbreviations, as applicable. A. Client-Side Entities

1. Northgate Telecommunications PLC, including all known subsidiaries and affiliates as identified in Northgate's most recent annual report filed with the London Stock Exchange and the U.S. Securities and Exchange Commission (Form 20-F).

2. NTP Acquisition Sub, Inc., a Delaware corporation (Delaware File No. 7301524; Employer Identification Number: 93-2587401), formed on February 21, 2025, as a direct wholly owned subsidiary of Northgate for the sole purpose of effecting the Merger.

3. Sir Malcolm Trent, KBE, Chief Executive Officer, Northgate Telecommunications PLC.

4. Gemma Haverford, Chief Financial Officer, Northgate Telecommunications PLC.

5. Philippa Ashworth, General Counsel, Northgate Telecommunications PLC.

6. Liam Sutherland, Vice President, Corporate Development, Northgate Telecommunications PLC; sole director of NTP Acquisition Sub, Inc.

7. Dame Catherine Enright, DBE, Chair of the Board of Directors, Northgate Telecommunications PLC.

8. Prumvane Brothers & Co., financial advisor to Northgate in connection with the proposed transaction. Lead managing director: Simone Favreau. Vice president on the engagement: Nathan Chu.

9. Hawthorne & Sable LLP, accounting and tax advisor to Northgate in connection with the proposed transaction. Engagement partner: Douglas Kirwan. Tax partner: Elena Montague. B. Target-Side Entities

1. Cascadia Fiber Networks, Inc., a Delaware corporation (Delaware File No. 5197843; Employer Identification Number: 45-6128937), with its principal executive offices located at 2750 NW Thurman Street, Suite 400, Portland, Oregon 97210. Cascadia is a privately held provider of fiber-optic telecommunications infrastructure and managed network services, with operations primarily in the Pacific Northwest region of the U

2. Derek Holmgren, Chief Executive Officer and Co-Founder, Cascadia Fiber Networks, Inc.

3. Priya Ramachandran, Chief Technology Officer and Co-Founder, Cascadia Fiber Networks, Inc.

4. Tobias Engel, Chief Financial Officer, Cascadia Fiber Networks, Inc.

5. Sandra Whitfield, General Counsel, Cascadia Fiber Networks, Inc.

6. Clive Atherton, Chair of the Board of Directors, Cascadia Fiber Networks, Inc. Mr. Atherton also serves as Managing Partner of Timberline Growth Management, LLC, the general partner of Timberline Growth Partners, LP (Cascadia's largest stockholder).

7. Rebecca Montrose, Director, Cascadia Fiber Networks, Inc. Ms. Montrose also serves as Managing Director of Ridgecrest Capital Management, LLC, the general partner of Ridgecrest Venture Fund III, LP (Cascadia's second-largest stockholder).

8. Gerald Foss, Independent Director, Cascadia Fiber Networks, Inc.

9. Diane Okamoto, Independent Director, Cascadia Fiber Networks, Inc.

10. Timberline Growth Partners, LP, holder of approximately 42.3% of the outstanding common stock of Cascadia. General Partner: Timberline Growth Management, LLC. Address: 888 SW Fifth Avenue, Suite 1500, Portland, Oregon 97204.

11. Ridgecrest Venture Fund III, LP, holder of approximately 17.8% of the outstanding common stock of Cascadia. General Partner: Ridgecrest Capital Management, LLC. Address: 101 California Street, Suite 3200, San Francisco, California 94111. C. Opposing / Target's Counsel

1. Whitmore, Kessler & Braun LLP, counsel to Cascadia and its board of directors in connection with the proposed transaction. Lead partner: Jonathan Kessler. Associate lead: Megan Tsai. Regulatory counsel: Aaron Whitmore. Address: 1120 SW Quelston Street, Suite 800, Portland, Oregon 97205.

2. Copperfield Zanthor & Partners, financial advisor to Cascadia and its board of directors in connection with the proposed transaction. Lead managing director: Paul Tremaine. Vice president on the engagement: Leah Gutierrez. Address: 555 Market Street, Suite 2600, San Francisco, California 94105. D. Financing Parties

1. Pinnacle Atlantic Bank, N.A., administrative agent and lead arranger of the $500,000,000 Acquisition Facility. Address: 270 Park Place, Charlotte, North Carolina 28202. Lead banker: Richard Dormer, Managing Director, Leveraged Finance. Pinnacle Atlantic's individual commitment under the Acquisition Facility is $200,000,000.

2. Commonwealth Trust Bank, syndicate lender under the Acquisition Facility. Commitment: $125,000,000.

3. Dralvecen National Bank, syndicate lender under the Acquisition Facility. Commitment: $100,000,000.

4. Elkhorn Capital Markets, LLC, syndicate lender under the Acquisition Facility ($75,000,000 commitment). Elkhorn also serves as the lender under Cascadia's existing term loan facility, under which approximately $82,600,000 in principal is currently outstanding.

5. Hargreaves & Liddell LLP, counsel to the lending syndicate (including Pinnacle Atlantic, Commonwealth Trust, Dralvecen National, and Elkhorn) in connection with the Acquisition Facility. Lead partner: Victoria Penn. Address: One Liberty Plaza, 48th Floor, New York, New York 10006. E. Other Transaction Parties

1. Clearfield Escrow Services, Inc., escrow agent for the transaction. Escrow officer: Martin Grieves. Address: 100 Wall Street, 20th Floor, New York, New York 10005.

2. Gresham Underwriting Group, Ltd., representations and warranties insurance broker. Address: 25 Old Broad Street, London EC2N 1HQ.

3. Marlowe Asset Management Specialty Insurance Co., representations and warranties insurance carrier. Address: 175 Water Street, 22nd Floor, New York, New York 10038.

4. Pemberton D&O Assurance, Ltd., directors' and officers' tail insurance carrier for the pre-closing period. Address: 71 Fenchurch Street, London EC3M 4BS.

5. Trident Transfer Agency, Inc., transfer and paying agent for the merger consideration. Address: 480 Washington Boulevard, Jersey City, New Jersey 07310.

6. Alderman Proxy Advisors, LLC, proxy solicitor (if stockholder vote is required). Address: 1407 Broadway, 27th Floor, New York, New York 10018.

7. Corporation Trust Associates, registered agent for NTP Acquisition Sub, Inc. in the State of Delaware. Address: 1209 Orange Street, Wilmington, Delaware 19801. F. Key Commercial Counterparties of Cascadia Based on information provided by Northgate and its financial advisor, the following key commercial counterparties of Cascadia were identified and included in the conflicts search due to the materiality of their c

1. Pacific Ridge Data Centers, LLC, counterparty to a master services agreement with Cascadia representing approximately $22,000,000 in annualized revenue. The master services agreement contains a change-of-control provision requiring the consent of Pacific Ridge to the consummation of the Merger.

2. Clearpath Internet Services, Inc., counterparty to a wholesale fiber indefeasible right of use ("IRU") agreement with Cascadia. The IRU agreement contains a change-of-control provision requiring the consent of Clearpath to the consummation of the Merger.

IV. Conflicts Database Search Results A. Methodology. A comprehensive search was conducted in the Calderwood & Harkness LLP Conflicts and New Business Intake System (the "CNB System") on February 24, 2025, at the direction of the undersigned. The search was performed using all entity names, trade names, short names, commonly used abbreviations, and individual names listed in Section III above, as well as any known al

V. Elkhorn Capital Markets, LLC — Dual Role Analysis and Waiver Protocol A. Identification of the Issue Elkhorn Capital Markets, LLC ("Elkhorn") occupies a dual role in the proposed transaction, which, together with the Firm's prior representation of Elkhorn, warrants specific analysis under the applicable rules of professional conduct: Role 1 — Existing Cascadia Lender. Elkhorn is the lender under Cascadia's existin

1. Client Disclosure. Philippa Ashworth, General Counsel of Northgate, has been informed in writing of Elkhorn's dual role in this transaction and of C&H's prior representation of Elkhorn in an unrelated matter. This disclosure was included in the engagement letter transmitted to Ms. Ashworth on February 26, 2025. The disclosure describes the nature and scope of C&H's prior relationship with Elkhorn, Elkhorn's dual r

2. Engagement Team Briefing. Although no formal ethical screen or information barrier is required — given that C&H does not currently represent Elkhorn and the prior representation is not substantially related to this matter — the engagement team has been briefed on Elkhorn's dual role and the Firm's prior relationship. Team members have been instructed that all communications with Elkhorn personnel in connection wit

3. Payoff Letter Coordination. The payoff letter for the Existing Elkhorn Facility will be coordinated between Cascadia (through its counsel, Whitmore, Kessler & Braun LLP) and Elkhorn (through its own counsel or internal legal department). C&H's involvement in the payoff process will be limited to reviewing the payoff letter from Northgate's perspective and ensuring that it satisfies the applicable closing condition

4. Ongoing Monitoring. The engagement team will actively monitor for any change in circumstances that could alter this conflicts assessment during the pendency of the transaction. Without limitation, the engagement team will monitor for and promptly escalate any of the following developments: (a) Elkhorn asserting claims against Cascadia under the Existing Elkhorn Facility prior to closing (e.g., claims of default or

VI. Additional Considerations In addition to the Elkhorn matter addressed in Section V above, the following parties and relationships were noted during the conflicts review process as warranting brief additional commentary, even though no conflicts were identified: A. Whitmore, Kessler & Braun LLP (Target's Counsel) Whitmore, Kessler & Braun LLP ("WKB") serves as counsel to Cascadia and its board of directors in conn

VII. Conclusion and Clearance Based on the comprehensive conflicts search conducted on February 24, 2025, and the detailed analysis set forth in this memorandum, this engagement is hereby cleared for conflicts purposes. The sole flagged item identified during the conflicts review — Elkhorn Capital Markets, LLC's dual role as (i) the lender under Cascadia's existing term loan facility (with approximately $82,600,000 i

VIII. Approval and Sign-Off Prepared by: Andrew Fitzpatrick Lead Associate, Mergers & Acquisitions Calderwood & Harkness LLP Reviewed by: Harrison Wexford Billing Partner, Mergers & Acquisitions Calderwood & Harkness LLP Approved by: Oliver Mackenzie Responsible Partner, Mergers & Acquisitions Calderwood & Harkness LLP REVIEWED AND APPROVED: By: ________ Name: Harrison Wexford Title: Billing Partner, Mergers & Acquis