Avidity Partners Management LP — REPLIGEN CORP RGEN: Quarterly 13F Position History
Avidity Partners Management LP has reported REPLIGEN CORP (RGEN) on 4 13F-HR filings in Pactolio's tracked window, first appearing in Q2 2025. As of Q1 2026, the position is sized at 77,800 shares ($9.2M market value, 2.08% of the equity book). Quarter-over-quarter share count change: + 27,500 (+54.7%) .
- 77,800Shares Held (Latest Filing)
- $9.2MReported Market Value (Latest Filing)
- 2.08%Portfolio Weight (% of 13F Equity Book)
- +27,500Quarter-over-Quarter Share Change
- +$962.4KQuarter-over-Quarter Value Change
- 106,500Peak Reported Shares (Historical)
Quarterly 13F-HR Disclosure History Source: SEC 13F-HR filings, 4 quarter s
| Quarter | Shares | QoQ Share Change | Share Change (%) | Market Value | Weight | Implied Price |
|---|---|---|---|---|---|---|
| Q1 2026 | 77,800 | +27,500 | +54.7% | $9.2M | 2.08% | $118.31 |
| Q4 2025 | 50,300 | +27,000 | +115.9% | $8.2M | 2.38% | $163.86 |
| Q3 2025 | 23,300 | 83,200 | -78.1% | $3.1M | 0.71% | $133.67 |
| Q2 2025 | 106,500 | — | — | $13.2M | 2.66% | $124.38 |
Methodology & FAQ
How This Position History Is Sourced
Each row is one SEC Form 13F-HR filing disclosing this position. Share count, market value, and reported quarter are taken verbatim from the filing; portfolio weight is recomputed against the same filing's total reported equity book. Implied price-per-share is market value divided by shares — a quarter-end mark, not the manager's cost basis. See the full methodology document for the normalization rules.
When did Avidity Partners Management LP first disclose a RGEN position in 13F-HR filings?
Avidity Partners Management LP first reported REPLIGEN CORP (RGEN) on its 13F-HR filing for the period ending 2025-06-30 (Q2 2025). The position has appeared on 4 reported quarters within Pactolio's tracked window.
What was Avidity Partners Management LP's most recent quarter-over-quarter share-count change in RGEN?
Between Q4 2025 and Q1 2026, Avidity Partners Management LP added 27,500 shares of RGEN (+54.7%), bringing the total reported position to 77,800 shares at a market value of $9.2M.
Does the implied price-per-share represent Avidity Partners Management LP's cost basis in RGEN?
No. The implied price-per-share column is the 13F-HR reported market value divided by reported share count on the filing date (end of quarter). It is a quarter-end mark, not a cost basis or transaction price. Use it as a sanity check on the value column, not as an indicator of the manager's entry or exit price.