Repligen Corporation (RGEN) Ownership
RGEN ownership summary
as of October 18, 2026- Institutions
- 106.6% of shares outstanding
- Insiders
- 4.66% of shares outstanding
- Shares outstanding
- 63.5M
- Float
- 53.5M shares available to trade
- Short interest
- 13.47% 7.6M shares short
- Days to cover
- 7.18 short interest up 12.9% vs prior month
- Institutions 106.64%
- Insiders 4.66%
RGEN top institutional holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | BlackRock Inc | 9.56% | 5.4M | $944.6M | −608,116 (−10.1%) | June 30, 2026 |
| 2 | FMR Inc | 5.91% | 3.3M | $583.6M | +439,904 (+15.2%) | June 30, 2026 |
| 3 | United Capital Financial Advisers Inc | 4.95% | 2.8M | $489.5M | +16,670 (+0.6%) | June 30, 2026 |
| 4 | Vanguard Capital Management, LLC | 4.28% | 2.4M | $423.0M | +14,660 (+0.6%) | June 30, 2026 |
| 5 | Vanguard Portfolio Management, LLC | 4.11% | 2.3M | $405.7M | +7,731 (+0.3%) | June 30, 2026 |
| 6 | Maverick Capital Ltd | 3.52% | 2.0M | $348.1M | +465,749 (+30.7%) | June 30, 2026 |
| 7 | State Street Corp | 3.20% | 1.8M | $315.8M | +23,245 (+1.3%) | June 30, 2026 |
| 8 | T. Rowe Price Associates, Inc. | 3.11% | 1.8M | $307.4M | −3.1M (−64.1%) | June 30, 2026 |
| 9 | Massachusetts Financial Services Company | 2.87% | 1.6M | $283.7M | +219,506 (+15.7%) | June 30, 2026 |
| 10 | Wasatch Advisors LP | 2.82% | 1.6M | $279.0M | +346,720 (+27.9%) | June 30, 2026 |
| 11 | Ameriprise Financial Inc | 2.80% | 1.6M | $276.5M | +650,918 (+70.4%) | June 30, 2026 |
| 12 | Bank of New York Mellon Corp | 2.70% | 1.5M | $267.1M | −8,543 (−0.6%) | June 30, 2026 |
| 13 | T. Rowe Price Investment Management,Inc. | 2.51% | 1.4M | $247.6M | +44,939 (+3.3%) | June 30, 2026 |
| 14 | Amvescap Plc. | 2.46% | 1.4M | $243.3M | +108,987 (+8.5%) | June 30, 2026 |
| 15 | Holocene Advisors, LP | 2.29% | 1.3M | $226.7M | +583,302 (+82.3%) | June 30, 2026 |
| 16 | RTW INVESTMENTS, LLC | 2.20% | 1.2M | $217.6M | +34,637 (+2.9%) | June 30, 2026 |
| 17 | Geode Capital Management, LLC | 1.89% | 1.1M | $186.4M | −1,981 (−0.2%) | June 30, 2026 |
| 18 | Congress Asset Management Company, LLP | 1.80% | 1.0M | $177.6M | +214,359 (+26.9%) | June 30, 2026 |
| 19 | Conestoga Capital Advisors, LLC | 1.74% | 981K | $172.1M | −116,800 (−10.6%) | June 30, 2026 |
| 20 | The Goldman Sachs Group Inc | 1.71% | 965K | $169.4M | +314,064 (+48.2%) | June 30, 2026 |
Value at the latest close. Change = shares bought or sold in the latest quarterly filing (13F). In the top 20, 15 holders added 3.5M shares and 5 cut 3.9M.
RGEN top mutual fund and ETF holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | iShares Core S&P Mid-Cap ETF | 3.57% | 2.0M | $352.6M | −720 (−0.0%) | September 30, 2026 |
| 2 | Vanguard MStar Total Stk Mkt Idx Invest | 3.02% | 1.7M | $298.5M | −6,563 (−0.4%) | August 31, 2026 |
| 3 | Vanguard Small Cap Index | 2.14% | 1.2M | $211.7M | −26,068 (−2.1%) | September 30, 2026 |
| 4 | MFS Mid Cap Growth A | 1.85% | 1.0M | $183.2M | +82,937 (+8.6%) | August 31, 2026 |
| 5 | T. Rowe Price New Horizons | 1.69% | 950K | $166.7M | −129,600 (−12.0%) | September 30, 2026 |
| 6 | Invesco Discovery A | 1.45% | 818K | $143.5M | +67,521 (+9.0%) | August 31, 2026 |
| 7 | American Funds SMALLCAP World A | 1.24% | 700K | $122.7M | +699,729 (0.0%) | September 30, 2026 |
| 8 | Wasatch Core Growth | 1.20% | 674K | $118.2M | +175,437 (+35.2%) | June 30, 2026 |
| 9 | Vanguard MStar Small Cap Growth Indx Inv | 1.19% | 671K | $117.7M | −36,906 (−5.2%) | September 30, 2026 |
| 10 | First Trust NYSE Arca Biotech ETF | 1.11% | 628K | $110.1M | — | September 30, 2026 |
| 11 | Fidelity Contrafund | 1.04% | 586K | $102.9M | +156,408 (+36.4%) | August 31, 2026 |
| 12 | Fidelity Select Health Care | 1.01% | 570K | $100.0M | +20,976 (+3.8%) | August 31, 2026 |
| 13 | Strategic Advisers Fidelity US TtlStk | 0.91% | 515K | $90.4M | +5,000 (+1.0%) | August 31, 2026 |
| 14 | Fidelity Select Medical Tech and Devcs | 0.89% | 500K | $87.7M | −19,500 (−3.8%) | August 31, 2026 |
| 15 | T. Rowe Price Small-Cap Stock | 0.84% | 473K | $83.0M | −14,990 (−3.1%) | September 30, 2026 |
| 16 | State Street® SPDR® S&P MIDCAP 400® ETF | 0.74% | 417K | $73.2M | +29,512 (+7.6%) | September 30, 2026 |
| 17 | iShares Biotechnology ETF | 0.74% | 416K | $72.9M | −3,152 (−0.8%) | September 30, 2026 |
| 18 | Columbia Small Cap Growth Inst | 0.71% | 398K | $69.9M | — | August 31, 2026 |
| 19 | Vanguard Explorer Inv | 0.70% | 394K | $69.2M | +56,178 (+16.6%) | June 30, 2026 |
| 20 | Congress Small Cap Growth Institutional | 0.68% | 385K | $67.5M | — | September 30, 2026 |
Funds report holdings monthly or quarterly; dates differ by fund.
RGEN insider transactions
latest 9| Date | Name | Transaction | Price | Shares | Value |
|---|---|---|---|---|---|
| 2025-12-17 | Karen A Dawes | Sell | $161.00 | 275 | $44,275 |
| 2025-11-18 | James Bylund | Sell | $151.21 | 2,191 | $331,301 |
| 2025-11-18 | James Bylund | Sell | $151.21 | 2,191 | $331,301 |
| 2025-11-13 | Anthony Hunt | Sell | $154.61 | 20,000 | $3.1M |
| 2025-11-12 | Anthony Hunt | Sell | $156.88 | 25,000 | $3.9M |
| 2025-10-31 | Lisa C. McClain | Sell | $149.06 | — | — |
| 2025-10-30 | Lisa C. McClain | Sell | $144.57 | — | — |
| 2025-10-30 | Lisa C. McClain | Buy | $144.57 | — | — |
| 2025-08-08 | Martin D Madaus | Buy | $112.13 | 1,800 | $201,834 |
Reported trades by company officers, directors and other filers (including disclosures by members of Congress where EODHD lists them). "—" where the filing gives no share count.
RGEN shares outstanding
Year-end shares outstanding, adjusted for splits.
Who owns RGEN
Institutional investors own 106.6% of Repligen's shares and insiders 4.66%. The largest holder is BlackRock Inc with 9.56% of the shares (5.4M), as of June 30, 2026. Among the top 20 institutions, 15 added shares and 5 reduced their stake in the latest filings. Short interest is 13.47% of the float, or 7.18 days of average trading volume. The share count rose 69.4% since 2014.
Related: RGEN analyst forecast, RGEN key metrics. See the RGEN stock overview for the latest quote and news.
RGEN ownership FAQ
Who owns the most Repligen stock?
The largest shareholders of Repligen are BlackRock Inc (9.56%), FMR Inc (5.91%), United Capital Financial Advisers Inc (4.95%), Vanguard Capital Management, LLC (4.28%), Vanguard Portfolio Management, LLC (4.11%).
What percentage of Repligen is owned by institutions?
Institutions hold 106.6% of Repligen's shares outstanding; insiders hold 4.66%.
Which funds own Repligen?
The largest fund holders of Repligen are iShares Core S&P Mid-Cap ETF (3.57%), Vanguard MStar Total Stk Mkt Idx Invest (3.02%), Vanguard Small Cap Index (2.14%), MFS Mid Cap Growth A (1.85%), T. Rowe Price New Horizons (1.69%).
What is Repligen's short interest?
7.6M shares of Repligen were sold short, 13.47% of the float; at the average daily volume it would take 7.18 days to cover.
Are insiders buying or selling Repligen?
Of the latest 9 reported insider transactions in Repligen (since August 8, 2025), 2 were purchases and 7 were sales.
How many shares of Repligen are outstanding?
Repligen has 63.5M shares outstanding, of which 53.5M are in the public float.