Welcome to our dedicated page for Prime Medicine SEC filings (Ticker: PRME), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
Prime Medicine, Inc. SEC filings document the biotechnology company's financial results, pipeline disclosures, governance matters and material events tied to its Prime Editing programs. Recent Form 8-K filings include Item 2.02 results releases, Regulation FD corporate presentations and Item 5.02 executive appointment disclosures, with exhibits summarizing business highlights for PM577 in Wilson Disease, PM647 in Alpha-1 Antitrypsin Deficiency and PM359 in chronic granulomatous disease.
Proxy materials disclose annual meeting matters, director elections, auditor ratification, executive compensation and equity-plan information. Together, the filings provide formal records of PRME's public-company governance, disclosure controls, capital and compensation arrangements, and regulatory-development communications for its genetic-medicine pipeline.
Prime Medicine (PRME) Form 4: Director Thomas Cahill reported a one-time repricing of four previously granted stock-option blocks on 08/01/2025. Options carrying exercise prices of $14.83 (39,062 shares) and $7.68 (45,000 shares) were cancelled (Code D) and simultaneously re-granted at $4.04 (Code A) for identical share amounts and original expirations (06/14/2033 and 06/12/2034, respectively). The new price equals PRME’s Nasdaq closing price on the repricing date, as approved by stockholders under the 2019 and 2022 equity plans. All vesting schedules and terms remain unchanged. Following the transactions, Cahill beneficially owns 84,062 options at the reduced strike, all held directly.
No open-market share movement or cash consideration occurred; the filing solely reflects the governance-approved adjustment intended to restore incentive value after a share-price decline.
Reine Allan, who is listed as both Chief Executive Officer and a director of Prime Medicine, reported a one-time repricing of certain outstanding stock options effective August 1, 2025. Stockholders approved reducing the per-share exercise price of the affected options to $4.04 from the prior $6.80, aligning the exercise price with the closing market price on the repricing date. The filing shows 850,000 options were repriced and remain governed by their original terms except for the new exercise price; these awards were issued under the 2019 and/or 2022 stock plans and retain their existing vesting schedules and expiration dates (noted as 01/17/2034). The repriced options become exercisable only as they vest and subject to continued service.
Transaction overview: On 08/01/2025 reporting person Alenson Carman filed a Form 4 disclosing a shareholder-approved one-time repricing of certain outstanding stock options under the Issuer's 2019 and/or 2022 equity plans. The Option Repricing reduced the per-share exercise price of the Repriced Options to $4.04, the Nasdaq closing price on the Repricing Date, and the filing states all other terms, including vesting and term, remain unchanged.
Scope and holdings: The filing lists repriced option grants totaling 203,333 underlying shares comprised of 16,083; 90,498; 6,254; and 90,498 share-equivalents. Original exercise prices shown are $10.92, $12.30, $13.63, and $8.49. Expiration dates range from 01/24/2032 to 02/21/2034. The Form is signed by attorney-in-fact Ryan Brown dated 08/05/2025.
On 01 Aug 2025, Prime Medicine, Inc. (PRME) received a Form 4 from its largest outside shareholder group, ARCH Venture Partners. Affiliate ARCH Venture Fund XII, L.P. executed an open-market purchase of 3,030,300 common shares at $3.30 (Transaction Code P). The buy lifts that fund’s direct position to 6,230,300 shares. Two related funds—ARCH Venture Fund X, L.P. and ARCH Venture Fund X Overage, L.P.—each continue to hold 6,128,297 shares. Taken together, the ARCH funds now report indirect beneficial ownership of more than 18 million PRME shares, maintaining their status as a 10% owner.
No derivative securities were involved and no sales were reported. The filing is part of a joint submission; a separate Form 4 covers shares held personally by ARCH co-founder Robert Nelsen. The sizable purchase at a single-digit share price signals continued confidence and long-term support from a strategic life-science investor.
Prime Medicine (PRME) – Form 4 insider transaction filed 08/01/2025. ARCH Venture entities, collectively 10% owners, disclosed a purchase of 3,030,300 common shares at $3.30 per share (approx. $10.0 million). The buyer of record is ARCH Venture Fund XII, L.P.
Post-transaction indirect holdings stand at:
- ARCH Venture Fund X, L.P.: 6,128,297 shares (unchanged)
- ARCH Venture Fund X Overage, L.P.: 6,128,297 shares (unchanged)
- ARCH Venture Fund XII, L.P.: 6,230,300 shares (up from zero disclosed in this filing)
Total indirect ownership across the reporting group rises to roughly 18.5 million shares. The filing is one of two joint reports; Robert Nelsen is filing separately for his direct holdings.
Key take-away: A sizable open-market purchase by a long-term venture backer at a depressed price signals increased confidence in PRME’s prospects and tightens insider alignment with public shareholders.