Robert Nelsen
About Robert Nelsen
Robert Nelsen (age 61 as of April 22, 2025) has served on Prime Medicine’s Board since September 2020 pursuant to ARCH Venture Partners’ right to appoint a board representative under a Voting Agreement tied to Prime’s preferred financings. He is co‑founder and Managing Director of ARCH Venture Partners, with decades of venture governance experience across public and private biotech. He holds an MBA from the University of Chicago and a BS in Economics and Biology from the University of Puget Sound .
Past Roles
| Organization | Role | Tenure | Committees/Impact |
|---|---|---|---|
| Revolution Healthcare Acquisition Corp | Director | 2021–Apr 2022 | — |
| Denali Therapeutics Inc. | Director | 2015–Jun 2022 | — |
| Unity Biotechnology, Inc. | Director | 2015–Dec 2020 | — |
| Agios Pharmaceuticals, Inc. | Director | 2007–Jun 2017 | — |
| Syros Pharmaceuticals, Inc. | Director | 2012–Jun 2018 | — |
| Juno Therapeutics, Inc. | Director | 2013–Mar 2018 | — |
| Sienna Biopharmaceuticals, Inc. | Director | 2015–Sep 2018 | — |
| Gossamer Bio, Inc. | Director (pre‑IPO) | 2017–Dec 2018 | — |
| Brii Biosciences Limited | Director | 2019–Jun 2024 | — |
External Roles
| Organization | Role | Tenure | Committees/Impact |
|---|---|---|---|
| Vir Biotechnology, Inc. | Director | Current | — |
| Sana Biotechnology, Inc. | Director | Current | — |
| Lyell Immunopharma, Inc. | Director | Current | — |
| Hua Medicine, Inc. | Director | Current | — |
Board Governance
- Independence: The Board determined in Feb 2025 that all directors except Keith Gottesdiener and Jeffrey Marrazzo are independent under Nasdaq and SEC rules; Nelsen is classified as independent despite ARCH affiliation .
- Committee assignments: Nelsen is a member of the Compensation Committee; not on Audit or Nominating & Corporate Governance .
- Attendance and engagement:
- Board met 6 times in 2024; all directors except Nelsen attended at least 75% of Board and applicable committee meetings .
- Board met 5 times in 2023; all directors except “Robert Nelson” (proxy typographical variation) attended at least 75% .
- Non‑employee directors met in executive session during each regularly scheduled Board meeting in 2024 and 2023 .
- Compensation Committee activity: Met 5 times in 2024; 10 times in 2023 .
- Audit Committee activity: Met 5 times in 2024; 5 times in 2023 .
- Board leadership: No Chair or Lead Independent Director designated; Board periodically reviews whether to appoint a Chair .
Fixed Compensation
| Year | Fees Earned or Paid in Cash ($) | Option Awards ($) | Total ($) |
|---|---|---|---|
| 2023 | 46,000 | 399,460 | 445,460 |
| 2024 | 50,063 | 237,528 | 287,591 |
Non‑Employee Director Compensation Policy highlights:
- Annual cash retainer increased from $40,000 to $45,000 in May 2024; committee retainers also increased (Audit Chair: $15k→$20k; Audit member: $7.5k→$10k; Comp Chair: $12k→$15k; Comp member: $6k→$7.5k) .
- Annual Director Option Grant: $400,000 value, capped at 45,000 shares; vests fully by 1 year or next annual meeting .
- Initial Director Option Grant: $800,000 value, capped at 90,000 shares; vests in equal annual installments over 3 years .
- Sale of Company: awards subject to fully accelerated vesting per 2024 policy .
Performance Compensation
| Performance Metric | Application to Director Compensation | Vesting/Terms |
|---|---|---|
| Performance-based metrics (e.g., revenue, EBITDA, TSR) | None disclosed for directors; director equity is non‑statutory stock options with time‑based vesting under policy | Annual grants vest fully by 1 year or next annual meeting; initial grants vest over 3 years; sale‑of‑company acceleration (2024 policy) |
Other Directorships & Interlocks
- Interlocks with major holders: ARCH Venture Partners (Nelsen affiliate) is an 11.78% holder; GV and Newpath are also >5% holders represented on the Board by other directors .
- Related party capital transactions:
- Follow‑on Offering (Feb 2024): ARCH affiliates purchased 3,200,000 shares for $20,000,000; GV 3,200,000 for $20,000,000; Newpath 800,000 for $5,000,000 .
- IPO (Oct 2022): ARCH 800,000 shares ($13.6M); GV 800,000 ($13.6M); Newpath 400,000 ($6.8M) .
- Series A (2019–2021 closings): ARCH affiliates purchased 33,333,331 preferred shares for $33,333,331 .
- Series B (2021): ARCH affiliates purchased 2,282,948 preferred shares for $9,999,997 .
- Appointment rights: Nelsen’s initial board seat came via ARCH’s contractual right under the Voting Agreement (Series A/B financings), indicating investor representation .
- Related party review: Audit Committee oversees and approves related person transactions; composed entirely of independent directors .
Expertise & Qualifications
- Venture governance and company-building across biotech (public and private), including Vir, Sana, Lyell, Hua Medicine .
- Advanced education: MBA (University of Chicago); BS in Economics/Biology (University of Puget Sound) .
- Board service stemming from investor representation and capital markets transactions (Voting Agreement context) .
Equity Ownership
| Holder | Shares Beneficially Owned | % of Outstanding | Notes |
|---|---|---|---|
| Robert Nelsen (individual line item) | 15,511,736 | 11.83% | As Committee Member of ARCH funds, may be deemed to share voting/disposition power; disclaims beneficial ownership except to pecuniary interest |
| Entities affiliated with ARCH Venture Partners (aggregate) | 15,456,594 | 11.78% | Composition: AVF X 6,128,297; AVF X Overage 6,128,297; AVF XII 3,200,000 |
| Shares outstanding (reference) | 131,160,842 (as of Mar 31, 2025) | — | — |
Options held by Nelsen (as of 12/31/2024): aggregate options to purchase 84,062 shares (annual grant of 45,000 in 2024; total options outstanding per director roll‑up) .
Trading, pledging, hedging: Company policy prohibits short sales, derivatives, and hedging transactions by directors; no pledging disclosures for Nelsen in the proxy .
Governance Assessment
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Strengths
- Deep biotech governance experience and capital markets connectivity; current public boards (Vir, Sana, Lyell, Hua) broaden sector insight .
- Material ownership alignment via ARCH affiliate stakes (11.78%) and Nelsen’s line‑item beneficial ownership (11.83%), though subject to fund‑level disclaimers .
- Compensation Committee independence and use of an independent consultant (Alpine Rewards) with no conflicts found; comp committee met 5 times (2024), indicating active oversight .
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Red flags and monitoring items
- Attendance: Nelsen did not attend ≥75% of Board/committee meetings in both 2024 and 2023—an engagement concern and renomination risk factor per Corporate Governance Guidelines .
- Investor‑affiliation conflicts: Board seat originated from ARCH’s Voting Agreement rights; ARCH participated in multiple related party capital raises (Series A/B, IPO, 2024 follow‑on). Audit Committee reviews such transactions, but continued monitoring of recusal practices and conflict management is warranted .
- No Chair/Lead Independent Director: Absence of formal independent leadership may reduce counterweight to investor‑affiliated directors; Board periodically reassesses leadership structure .
-
Director pay mix trend: Y/Y shift toward higher cash retainers and lower equity option accounting values (2023→2024), consistent with May 2024 policy increases in cash retainers; annual option grant cap maintained at 45,000 shares .
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Independence validation: Board deemed Nelsen independent despite affiliations; explicitly considered beneficial ownership and facts relevant to independence under Nasdaq/SEC standards .
Overall, Nelsen brings valuable sector and financing expertise with significant ownership alignment via ARCH, but his sub‑75% attendance in consecutive years is a meaningful governance red flag that could affect investor confidence; continued scrutiny of related‑party dealings and attendance improvement would mitigate risk .