Third Rock Ventures V, LP

10% owner Third Rock Ventures V sells 133,618 shares for $5.4M; 4th sale at RAPP in 36 months with consistent prior exits well-timed as stock fell after each.

Third Rock Ventures V, a significant 10% beneficial owner, is shedding shares for the fourth time in the past three years—a pattern of repeated exits rather than accumulation. This latest sale occurred at a modest premium to the stock's recent trading range, and the fund's prior three exits at RAPP all proved well-timed, with the stock declining following each one, suggesting disciplined capital allocation. Rapport itself remains unprofitable with mounting quarterly losses, and while the stock has rallied notably in recent months, it still trades below its 52-week high. The fund's consistent exits here—now representing a reduction of over 2% of Third Rock Ventures V's original stake—underscore an institutional perspective: rebalancing a holding in a loss-making biotech rather than conviction-level accumulation typical of insider buyers betting on turnaround momentum.

Third Rock Ventures V (10% owner) sells 276k shares for $11.1M; first exit since well-timed prior sale, but stock up significantly in recent months.

L.P. Third Rock Ventures V, a significant institutional holder with over 10% ownership, divested a modest 4.1% of its stake across two sales in early May. The fund's prior sale at this company was well-timed—shares declined afterward—setting a positive precedent for exit decisions. However, this current sale arrives after the stock has gained substantially over recent months and still trades below its 52-week high, an environment where exits traditionally signal less urgency. The company remains unprofitable with mounting losses, though it generated meaningful quarterly revenue, creating a mixed fundamental backdrop. For a portfolio manager of this scale, modest portfolio rebalancing is routine, though the timing—after significant recent gains—suggests a pragmatic trim rather than alarm about deteriorating fundamentals or imminent business deterioration.

10% owner Third Rock Ventures V sold 426,005 shares of RAPP at $40.32 (17.2M); stock now -7.0% from 52-week high; company unprofitable.

Third Rock Ventures V, a 10% owner, sold 426,005 shares at $40.32 on 2026-04-17 for $17,175,243.59, reducing its stake from 7.14M to 6.71M shares (-6.0%). The sale occurred at a price well above the current market price of $36.95 and near the 52-week high of $39.71, suggesting the insider executed the sale at a relatively advantageous recent price level. However, context is important: the stock has risen substantially (+36.4% in 30 days, +40.0% in 90 days) from depressed levels, and RAPP remains unprofitable with a full-year net income of -$26.9M. This is a material reduction in a significant position by a major investor, and the timing relative to the company's fundamental weakness and recent price recovery invites scrutiny of valuation fundamentals. The insider retains 6.71M shares, maintaining substantial exposure.

Third Rock Ventures V acquires 650,000 SEPN shares for $11,700,000 in 2 purchases at $18.00; post-transaction holdings reach 3,152,456 shares

Third Rock Ventures V, a 10% owner, executed 2 separate purchases totaling 650,000 shares for $11,700,000 at $18.00 on 2024-10-28, increasing holdings by 26.0% from 2,502,456 to 3,152,456 shares. The purchase occurred at $18.00 while current price stands at $20.75—a 15.3% premium to the transaction price. This transaction occurs in early stages of the company's public life (RECENT LISTING with only 2 trading days of history), where 52-week metrics are not yet meaningful. The substantial size ($11.7M) and staged execution across two transactions suggests deliberate accumulation by a significant existing stakeholder, though the actual basis for this decision cannot be determined from filing data alone.