Ultragenyx Pharmaceutical Inc. (RARE) Ownership
RARE ownership summary
as of October 18, 2026- Institutions
- 112.7% of shares outstanding
- Insiders
- 3.44% of shares outstanding
- Shares outstanding
- 98.6M
- Float
- 80.4M shares available to trade
- Short interest
- 21.35% 20.3M shares short
- Days to cover
- 2.95 short interest up 22.8% vs prior month
- Institutions 112.73%
- Insiders 3.44%
RARE top institutional holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | BlackRock Inc | 10.81% | 10.7M | $154.9M | +3.4M (+46.0%) | June 30, 2026 |
| 2 | RTW INVESTMENTS, LLC | 7.91% | 7.8M | $113.4M | +4.1M (+113.7%) | June 30, 2026 |
| 3 | Vanguard Portfolio Management, LLC | 6.89% | 6.8M | $98.7M | +1.4M (+26.1%) | June 30, 2026 |
| 4 | AQR Capital Management LLC | 6.65% | 6.6M | $95.4M | +2.0M (+43.3%) | June 30, 2026 |
| 5 | State Street Corp | 6.25% | 6.2M | $89.5M | +1.1M (+22.6%) | June 30, 2026 |
| 6 | Vanguard Capital Management, LLC | 4.36% | 4.3M | $62.5M | +106,660 (+2.5%) | June 30, 2026 |
| 7 | Two Sigma Investments LLC | 3.67% | 3.6M | $52.7M | +1.4M (+64.2%) | June 30, 2026 |
| 8 | Sands Capital Management, LLC | 3.20% | 3.2M | $45.9M | −56,165 (−1.7%) | June 30, 2026 |
| 9 | Jacobs Levy Equity Management, Inc. | 2.98% | 2.9M | $42.7M | +1.5M (+105.4%) | June 30, 2026 |
| 10 | Frontier Capital Management CO Inc | 2.89% | 2.8M | $41.4M | +656,754 (+30.0%) | June 30, 2026 |
| 11 | Geode Capital Management, LLC | 2.62% | 2.6M | $37.5M | +729,437 (+39.4%) | June 30, 2026 |
| 12 | Bellevue Group AG | 2.01% | 2.0M | $28.8M | −397,225 (−16.7%) | June 30, 2026 |
| 13 | D. E. Shaw & Co LP | 1.75% | 1.7M | $25.2M | +469,175 (+37.2%) | June 30, 2026 |
| 14 | Sofinnova Ventures | 1.74% | 1.7M | $25.0M | −1.4M (−45.4%) | June 30, 2026 |
| 15 | Adage Capital Partners Gp LLC | 1.60% | 1.6M | $23.0M | +1.1M (+229.2%) | June 30, 2026 |
| 16 | GW&K Investment Management, LLC | 1.50% | 1.5M | $21.5M | −134,248 (−8.3%) | June 30, 2026 |
| 17 | MPM Oncology Impact Management LP | 1.44% | 1.4M | $20.6M | +1.4M (0.0%) | June 30, 2026 |
| 18 | T. Rowe Price Associates, Inc. | 1.38% | 1.4M | $19.7M | +552,392 (+68.7%) | June 30, 2026 |
| 19 | Morgan Stanley - Brokerage Accounts | 1.34% | 1.3M | $19.3M | −175,723 (−11.7%) | June 30, 2026 |
| 20 | Wellington Management Company LLP | 1.27% | 1.3M | $18.2M | −1.4M (−52.6%) | June 30, 2026 |
Value at the latest close. Change = shares bought or sold in the latest quarterly filing (13F). In the top 20, 14 holders added 20.0M shares and 6 cut 3.6M.
RARE top mutual fund and ETF holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | State Street® SPDR® S&P® Biotech ETF | 5.20% | 5.1M | $74.6M | −98,050 (−1.9%) | September 30, 2026 |
| 2 | Vanguard MStar Total Stk Mkt Idx Invest | 3.04% | 3.0M | $43.6M | −6,147 (−0.2%) | August 31, 2026 |
| 3 | iShares Russell 2000 ETF | 2.53% | 2.5M | $36.3M | −28,800 (−1.1%) | September 30, 2026 |
| 4 | Vanguard Small Cap Index | 2.14% | 2.1M | $30.7M | −42,174 (−2.0%) | September 30, 2026 |
| 5 | Vanguard MStar Small Cap Growth Indx Inv | 1.19% | 1.2M | $17.1M | −58,404 (−4.7%) | September 30, 2026 |
| 6 | Vanguard Strategic Equity Inv | 1.09% | 1.1M | $15.6M | +289,565 (+37.0%) | June 30, 2026 |
| 7 | Fidelity Small Cap Index | 1.07% | 1.1M | $15.3M | +8,934 (+0.9%) | July 31, 2026 |
| 8 | AQR Long-Short Equity I | 0.93% | 915K | $13.3M | +103,277 (+12.7%) | June 30, 2026 |
| 9 | Candriam Eqs L Biotech C USD Cap | 0.84% | 827K | $12.0M | — | March 31, 2026 |
| 10 | Vanguard Explorer Inv | 0.83% | 822K | $12.0M | −899,191 (−52.2%) | June 30, 2026 |
| 11 | Carillon Scout Mid Cap I | 0.75% | 743K | $10.8M | +743,419 (0.0%) | September 30, 2026 |
| 12 | iShares Biotechnology ETF | 0.71% | 702K | $10.2M | −5,312 (−0.8%) | September 30, 2026 |
| 13 | Vanguard Russell 2000 ETF | 0.57% | 562K | $8.2M | +6,330 (+1.1%) | September 30, 2026 |
| 14 | Polar Capital Biotech S Inc | 0.53% | 525K | $7.6M | — | December 31, 2025 |
| 15 | Schwab US Small-Cap ETF™ | 0.53% | 521K | $7.6M | +351 (+0.1%) | September 30, 2026 |
| 16 | Strategic Advisers U.S. Total Stock | 0.52% | 511K | $7.4M | +8,394 (+1.7%) | August 31, 2026 |
| 17 | iShares Russell 2000 Value ETF | 0.51% | 499K | $7.3M | +756 (+0.2%) | September 30, 2026 |
| 18 | Fidelity Extended Market Index | 0.49% | 487K | $7.1M | −3,769 (−0.8%) | August 31, 2026 |
| 19 | Vanguard Strategic Small-Cap Equity Inv | 0.49% | 479K | $7.0M | +242,437 (+102.4%) | June 30, 2026 |
| 20 | Fidelity Enhanced Small Cap Core ETF | 0.44% | 433K | $6.3M | +909 (+0.2%) | September 30, 2026 |
Funds report holdings monthly or quarterly; dates differ by fund.
RARE insider transactions
latest 20| Date | Name | Transaction | Price | Shares | Value |
|---|---|---|---|---|---|
| 2026-04-01 | Howard Horn | Sell | $20.97 | 4,683 | $98,203 |
| 2026-03-03 | Howard Horn | Sell | $22.40 | 1,635 | $36,624 |
| 2026-03-03 | Gilbert Ray Cisneros, Jr. | Buy | $22.07 | — | — |
| 2026-03-02 | Emil D Kakkis | Sell | $22.80 | 54,404 | $1.2M |
| 2026-03-02 | Eric Crombez | Sell | $22.80 | 7,029 | $160,261 |
| 2026-03-02 | Erik Harris | Sell | $22.80 | 10,539 | $240,289 |
| 2026-03-02 | Howard Horn | Sell | $22.70 | 8,409 | $190,884 |
| 2026-03-02 | John Richard Pinion | Sell | $22.80 | 10,029 | $228,661 |
| 2026-03-02 | Karah Herdman Parschauer | Sell | $22.80 | 8,135 | $185,478 |
| 2026-03-02 | Theodore Alan Huizenga | Sell | $22.80 | 1,632 | $37,210 |
| 2026-02-18 | Gilbert Ray Cisneros, Jr. | Buy | $20.45 | — | — |
| 2026-02-02 | Howard Horn | Sell | $23.56 | 3,061 | $72,117 |
| 2025-12-29 | Theodore Alan Huizenga | Sell | $34.38 | 85 | $2,922 |
| 2025-12-10 | Howard Horn | Sell | $36.38 | 3,081 | $112,087 |
| 2025-10-13 | Howard Horn | Sell | $31.51 | 7,942 | $250,252 |
| 2025-09-18 | Theodore Alan Huizenga | Sell | $29.17 | 64 | $1,867 |
| 2025-09-12 | Karah Herdman Parschauer | Sell | $31.17 | 2,450 | $76,366 |
| 2025-08-08 | Gilbert Ray Cisneros, Jr. | Buy | $27.54 | — | — |
| 2025-07-15 | Gilbert Ray Cisneros, Jr. | Buy | $27.20 | — | — |
| 2025-06-20 | Corazon (Corsee) D Sanders | Sell | $37.39 | 2,405 | $89,923 |
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.
RARE shares outstanding
Year-end shares outstanding, adjusted for splits.
Who owns RARE
Institutional investors own 112.7% of Ultragenyx Pharmaceutical's shares and insiders 3.44%. The largest holder is BlackRock Inc with 10.81% of the shares (10.7M), as of June 30, 2026. Among the top 20 institutions, 14 added shares and 6 reduced their stake in the latest filings. Short interest is 21.35% of the float, or 2.95 days of average trading volume. The share count rose 213.2% since 2014.
Related: RARE analyst forecast, RARE key metrics. See the RARE stock overview for the latest quote and news.
RARE ownership FAQ
Who owns the most Ultragenyx Pharmaceutical stock?
The largest shareholders of Ultragenyx Pharmaceutical are BlackRock Inc (10.81%), RTW INVESTMENTS, LLC (7.91%), Vanguard Portfolio Management, LLC (6.89%), AQR Capital Management LLC (6.65%), State Street Corp (6.25%).
What percentage of Ultragenyx Pharmaceutical is owned by institutions?
Institutions hold 112.7% of Ultragenyx Pharmaceutical's shares outstanding; insiders hold 3.44%.
Which funds own Ultragenyx Pharmaceutical?
The largest fund holders of Ultragenyx Pharmaceutical are State Street® SPDR® S&P® Biotech ETF (5.20%), Vanguard MStar Total Stk Mkt Idx Invest (3.04%), iShares Russell 2000 ETF (2.53%), Vanguard Small Cap Index (2.14%), Vanguard MStar Small Cap Growth Indx Inv (1.19%).
What is Ultragenyx Pharmaceutical's short interest?
20.3M shares of Ultragenyx Pharmaceutical were sold short, 21.35% of the float; at the average daily volume it would take 2.95 days to cover.
Are insiders buying or selling Ultragenyx Pharmaceutical?
Of the latest 20 reported insider transactions in Ultragenyx Pharmaceutical (since June 20, 2025), 4 were purchases and 16 were sales.
How many shares of Ultragenyx Pharmaceutical are outstanding?
Ultragenyx Pharmaceutical has 98.6M shares outstanding, of which 80.4M are in the public float.