MIRUM PHARMACEUTICALS INC MIRM
COM · Common Stock · CUSIP 604749101 · ISIN US6047491013
Biopharmaceutical company
- SectorHealth care
- IndustryPharmaceutical Preparations
- HeadquartersFoster City, CA
- Founded2018
- Websitemirumpharma.com
- FilingsSEC EDGAR
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once ($4.4m this quarter). Holder counts are more reliable. Shares outstanding: 61.0m as of 2026-05-01, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $92.22. Options: 5 managers hold calls ($19.9m notional), 4 hold puts ($1.5m).
Trends to Q1 2026
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2022 | 112 |
| Q4 2022 | 105 |
| Q1 2023 | 119 |
| Q2 2023 | 148 |
| Q3 2023 | 161 |
| Q4 2023 | 189 |
| Q1 2024 | 174 |
| Q2 2024 | 163 |
| Q3 2024 | 180 |
| Q4 2024 | 207 |
| Q1 2025 | 216 |
| Q2 2025 | 216 |
| Q3 2025 | 273 |
| Q4 2025 | 285 |
| Q1 2026 | 312 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q2 2024 | 88 | 83 |
| Q3 2024 | 108 | 60 |
| Q4 2024 | 105 | 76 |
| Q1 2025 | 117 | 87 |
| Q2 2025 | 111 | 112 |
| Q3 2025 | 160 | 90 |
| Q4 2025 | 150 | 120 |
| Q1 2026 | 176 | 123 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q2 2025 | $1.5m | $5.1m | 3.27 |
| Q3 2025 | $7.2m | $7.7m | 1.08 |
| Q4 2025 | $4.5m | $876.8k | 0.19 |
| Q1 2026 | $19.9m | $1.5m | 0.08 |
Biggest buyers
| FMR LLC | Added | +1.3m |
| TCG Crossover Management, LLC | Added | +1.0m |
| Frazier Life Sciences Management, L.P. | Added | +884.6k |
| JANUS HENDERSON GROUP PLC | Added | +880.5k |
| Capital World Investors | New | +724.4k |
| Paradigm Biocapital Advisors LP | New | +625.0k |
| BAKER BROS. ADVISORS LP | New | +446.0k |
| TWO SIGMA INVESTMENTS, LP | Added | +386.3k |
| Octagon Capital Advisors LP | New | +338.9k |
| RA CAPITAL MANAGEMENT, L.P. | New | +318.6k |
Biggest sellers
| D. E. Shaw & Co., Inc. | Reduced | -780.7k |
| EVENTIDE ASSET MANAGEMENT, LLC | Reduced | -684.7k |
| Polar Capital Holdings Plc | Reduced | -510.2k |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP | Reduced | -304.6k |
| PERCEPTIVE ADVISORS LLC | Sold out | -259.5k |
| TWO SIGMA ADVISERS, LP | Sold out | -232.1k |
| STATE STREET CORP | Reduced | -199.7k |
| Clearbridge Investments, LLC | Reduced | -194.1k |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC | Reduced | -193.9k |
| ALGERT GLOBAL LLC | Sold out | -174.2k |
Biggest calls
| Caption Management, LLC | New | $9.2m100.0k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $9.0m97.2k shares |
| CITADEL ADVISORS LLC | Reduced | $1.1m11.5k shares |
| JANE STREET GROUP, LLC | Added | $591.2k6.4k shares |
| SIMPLEX TRADING, LLC | Reduced | $64.7k700 shares |
Biggest puts
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | New | $609.7k6.6k shares |
| Point72 Asset Management, L.P. | Reduced | $609.7k6.6k shares |
| JANE STREET GROUP, LLC | Unchanged | $267.9k2.9k shares |
| SIMPLEX TRADING, LLC | New | $37.0k400 shares |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
| Janus Henderson Group Ltd. 13G · institution -2.1 pts · filed 2026-08-13 | 9.7% |
Frazier Life Sciences IX, L.P.
13D · may seek influence
-0.8 pts · filed 2026-01-27
Stated purposeItem 4 is hereby amended and restated in its entirety to read as follows: Each of FLS IX, FLS X, FLSPF, FLS XI and FLS XII acquired the FLS IX Shares, the FLS X Shares, the FLSPF Shares, the FLS XI Shares and the FLS XII Shares, as the case may be, for investment purposes. Depending on market conditions, its continuing evaluation of the business and prospects of the Issuer and other factors, FLS IX, FLS X, FLSPF, FLS XI and FLS XII and the other Reporting Persons may dispose of or acquire additional shares of the Issuer. Except as set forth above, none of the Reporting Persons has any present plans which relate to or would result in: (a) The acquisition by any person of additional securities of the Issuer, or the disposition of securities of the Issuer; (b) An extraordinary corporat… Full filing |
6.8% |
| FMR LLC 13G · institution new · filed 2026-08-06 | 6.2% |
| BlackRock, Inc. 13G · institution filed 2026-04-27 | 5.7% |
Fell to 5% or below in the last year: VANGUARD GROUP INC (0.0%, 2026-03-27), EVENTIDE ASSET MANAGEMENT, LLC (4.1%, 2026-02-13), BIOTECHNOLOGY VALUE FUND L P (3.0%, 2025-11-14)
Insider purchases and sales in Q1 2026
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q2 2024 | 0 | — | 2 | $1.2m | $1.2m |
| Q3 2024 | 1 | $13.9k | 1 | $12.8k | — |
| Q4 2024 | 0 | — | 1 | $117.8k | — |
| Q1 2025 | 1 | $280.1k | 4 | $8.7m | $4.5m |
| Q2 2025 | 0 | — | 2 | $532.9k | — |
| Q3 2025 | 0 | — | 5 | $7.3m | $5.3m |
| Q4 2025 | 0 | — | 2 | $11.6m | $11.6m |
| Q1 2026 | 1 | $9.0m | 6 | $11.3m | $567.7k |
| Date | Insider | Trade | Value |
|---|---|---|---|
| 2026-03-16 | Peetz Christopher CHIEF EXECUTIVE OFFICER, director | Sold | $3.8m41.0k shares |
| 2026-03-16 | Radovich Peter PRESIDENT AND COO | Sold | $1.5m16.5k shares |
| 2026-03-16 | Quan Joanne CHIEF MEDICAL OFFICER | Sold | $670.3k7.3k shares |
| 2026-03-16 | BJERKHOLT ERIC CHIEF FINANCIAL OFFICER | Sold | $670.3k7.3k shares |
| 2026-03-16 | Howe Jolanda SVP, GLOBAL CONTROLLER | Sold | $435.2k4.7k shares |
| 2026-03-16 | Ramasastry Saira Director | Sold plan | $181.5k2.0k shares |
| 2026-02-13 | Ramasastry Saira Director | Sold plan | $204.2k2.0k shares |
| 2026-02-02 | Peetz Christopher CHIEF EXECUTIVE OFFICER, director | Sold | $940.9k9.1k shares |
| 2026-02-02 | Radovich Peter PRESIDENT AND COO | Sold | $271.8k2.6k shares |
| 2026-02-02 | Howe Jolanda SVP, GLOBAL CONTROLLER | Sold | $100.0k968 shares |
| 2026-01-26 | Peetz Christopher CHIEF EXECUTIVE OFFICER, director | Sold | $657.1k6.8k shares |
| 2026-01-26 | Radovich Peter PRESIDENT AND COO | Sold | $302.3k3.1k shares |
| 2026-01-26 | BJERKHOLT ERIC CHIEF FINANCIAL OFFICER | Sold | $101.3k1.1k shares |
| 2026-01-26 | Howe Jolanda SVP, GLOBAL CONTROLLER | Sold | $81.0k842 shares |
| 2026-01-23 | Heron Patrick J Director · By Frazier Life Sciences X, L.P. | Bought | $9.0m131.4k shares |
| 2026-01-22 | Peetz Christopher CHIEF EXECUTIVE OFFICER, director | Sold | $662.5k7.1k shares |
| 2026-01-22 | Radovich Peter PRESIDENT AND COO | Sold | $222.3k2.4k shares |
| 2026-01-22 | Quan Joanne CHIEF MEDICAL OFFICER | Sold | $170.0k1.8k shares |
| 2026-01-22 | BJERKHOLT ERIC CHIEF FINANCIAL OFFICER | Sold | $132.6k1.4k shares |
| 2026-01-22 | Howe Jolanda SVP, GLOBAL CONTROLLER | Sold | $86.4k926 shares |
| 2026-01-20 | Quan Joanne CHIEF MEDICAL OFFICER | Sold | $623.9k6.9k shares |
| 2026-01-15 | Ramasastry Saira Director | Sold plan | $182.0k2.0k shares |
Their holding: how much the trade added to or took from the insider's holding (direct, or the trust or fund named). The same trade is sometimes reported by more than one insider, such as a fund and the director who represents it; totals count it once. A value is left blank where the reported price is far from the market price (usually a typo).
Holders, Q1 2026
| Manager | Shares | Change |
|---|---|---|
| Frazier Life Sciences Management, L.P. 18.25% of their portfolio | 7.7m $709.4m | Added +884.6k |
| JANUS HENDERSON GROUP PLC 0.31% of their portfolio | 6.9m $641.8m | Added +880.5k |
| BlackRock, Inc. 0.01% of their portfolio | 3.8m $355.3m | Added +201.2k |
| VANGUARD CAPITAL MANAGEMENT LLC 0.01% of their portfolio | 2.4m $223.1m | First filing |
| FMR LLC 0.01% of their portfolio | 2.0m $181.6m | Added +1.3m |
| STATE STREET CORP 0.01% of their portfolio | 1.9m $179.6m | Reduced -199.7k |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.02% of their portfolio | 1.7m $158.7m | Added +297.0k |
| BVF INC/IL 4.66% of their portfolio | 1.6m $146.4m | Added +89.4k |
| VANGUARD PORTFOLIO MANAGEMENT LLC 0.01% of their portfolio | 1.4m $132.3m | First filing |
| EVENTIDE ASSET MANAGEMENT, LLC 2.15% of their portfolio | 1.4m $130.1m | Reduced -684.7k |
| WELLINGTON MANAGEMENT GROUP LLP 0.02% of their portfolio | 1.3m $123.3m | Added +97.0k |
| NOVO HOLDINGS A/S 9.92% of their portfolio | 1.3m $122.4m | Added +61.0k |
| GEODE CAPITAL MANAGEMENT, LLC 0.01% of their portfolio | 1.3m $116.4m | Added +197.1k |
| TANG CAPITAL MANAGEMENT LLC 5.80% of their portfolio | 1.2m $114.2m | Unchanged |
| TCG Crossover Management, LLC 2.81% of their portfolio | 1.1m $98.1m | Added +1.0m |
| CITADEL ADVISORS LLC 0.07% of their portfolio | 1.1m $97.2m | Added +211.8k |
| BNP PARIBAS FINANCIAL MARKETS 0.06% of their portfolio | 911.4k $84.2m | Added +255.6k |
| Rock Springs Capital Management LP 4.42% of their portfolio | 811.3k $74.9m | Added +49.0k |
| TWO SIGMA INVESTMENTS, LP 0.06% of their portfolio | 774.8k $71.6m | Added +386.3k |
| Capital World Investors 0.01% of their portfolio | 724.4k $66.9m | New |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 722.2k $66.7m | Added +8.7k |
| FRANKLIN RESOURCES INC 0.02% of their portfolio | 714.8k $66.0m | Added +64.1k |
| Clearbridge Investments, LLC 0.05% of their portfolio | 671.9k $62.1m | Reduced -194.1k |
| GOLDMAN SACHS GROUP INC 0.01% of their portfolio | 662.3k $61.2m | Reduced -62.0k |
| Paradigm Biocapital Advisors LP 1.18% of their portfolio | 625.0k $57.7m | New |
| LORD, ABBETT & CO. LLC 0.19% of their portfolio | 617.1k $57.0m | Added +37.1k |
| Bank of New York Mellon Corp 0.01% of their portfolio | 584.5k $54.0m | Added +18.9k |
| RENAISSANCE TECHNOLOGIES LLC 0.08% of their portfolio | 582.1k $53.8m | Added +143.0k |
| Woodline Partners LP 0.20% of their portfolio | 567.9k $52.5m | Unchanged |
| Balyasny Asset Management L.P. 0.10% of their portfolio | 539.0k $49.8m | Added +253.2k |
| MORGAN STANLEY 0.00% of their portfolio | 524.6k $48.5m | Added +98.9k |
| FEDERATED HERMES, INC. 0.08% of their portfolio | 506.2k $46.8m | Added +24.2k |
| UBS Group AG 0.01% of their portfolio | 495.0k $45.7m | Added +174.2k |
| Connor, Clark & Lunn Investment Management Ltd. 0.10% of their portfolio | 479.5k $44.3m | Reduced -42.2k |
| LOOMIS SAYLES & CO L P 0.06% of their portfolio | 475.3k $43.9m | Reduced -39.7k |
| Nuveen, LLC 0.01% of their portfolio | 474.2k $43.8m | Reduced -28.8k |
| Candriam S.C.A. 0.22% of their portfolio | 464.2k $42.9m | Reduced -105.4k |
| BAKER BROS. ADVISORS LP 0.24% of their portfolio | 446.0k $41.2m | New |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.01% of their portfolio | 427.1k $39.5m | Added +17.8k |
| Pictet Asset Management Holding SA 0.04% of their portfolio | 423.5k $39.1m | Reduced -153.8k |
| BOONE CAPITAL MANAGEMENT LLC 11.92% of their portfolio | 421.2k $38.9m | Unchanged |
| NOMURA ASSET MANAGEMENT INTERNATIONAL INC. 0.06% of their portfolio | 405.3k $37.4m | Reduced -16.5k |
| First Turn Management, LLC 4.13% of their portfolio | 400.5k $37.0m | Reduced -81.1k |
| Soleus Capital Management, L.P. 1.50% of their portfolio | 400.3k $37.0m | Reduced -173.3k |
| EMERALD ADVISERS, LLC 1.16% of their portfolio | 397.3k $36.7m | Added +30.1k |
| NORTHERN TRUST CORP 0.00% of their portfolio | 394.9k $36.5m | Added +20.1k |
| NEXT CENTURY GROWTH INVESTORS LLC 2.58% of their portfolio | 385.5k $35.6m | Added +17.5k |
| TimesSquare Capital Management, LLC 0.59% of their portfolio | 376.5k $34.8m | Reduced -19.4k |
| ADAGE CAPITAL PARTNERS GP, L.L.C. 0.05% of their portfolio | 375.0k $34.6m | Reduced -92.5k |
| MILLENNIUM MANAGEMENT LLC 0.03% of their portfolio | 368.6k $34.0m | Added +124.3k |
| Point72 Asset Management, L.P. 0.06% of their portfolio | 347.0k $32.1m | Added +156.4k |
| Octagon Capital Advisors LP 3.46% of their portfolio | 338.9k $31.3m | New |
| WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC 0.10% of their portfolio | 335.7k $31.0m | Reduced -1.0k |
| VANGUARD FIDUCIARY TRUST CO 0.01% of their portfolio | 333.3k $30.8m | First filing |
| Trails Edge Capital Partners, LP 7.25% of their portfolio | 333.3k $30.8m | Added +301.4k |
| Palo Alto Investors LP 4.59% of their portfolio | 325.2k $30.0m | Added +168.8k |
| RA CAPITAL MANAGEMENT, L.P. 0.31% of their portfolio | 318.6k $29.4m | New |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ 0.01% of their portfolio | 286.4k $26.5m | New |
| Hood River Capital Management LLC 0.26% of their portfolio | 285.4k $26.4m | Added +5.4k |
| Invesco Ltd. 0.00% of their portfolio | 285.2k $26.4m | Added +220.3k |
| Polar Capital Holdings Plc 0.11% of their portfolio | 283.5k $26.2m | Reduced -510.2k |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. 0.03% of their portfolio | 265.6k $24.5m | Added +8.4k |
| Penn Capital Management Company, LLC 1.84% of their portfolio | 256.8k $23.8m | Reduced -25.2k |
| EMERALD MUTUAL FUND ADVISERS TRUST 1.12% of their portfolio | 250.4k $23.1m | Added +8.1k |
| NAN FUNG TRINITY (HK) LTD 2.36% of their portfolio | 232.7k $21.5m | Added +5.2k |
| Patient Square Capital LP 3.77% of their portfolio | 230.0k $21.2m | Reduced -68.7k |
| RAYMOND JAMES FINANCIAL INC 0.01% of their portfolio | 228.2k $21.1m | Reduced -18.2k |
| AMERIPRISE FINANCIAL INC 0.00% of their portfolio | 219.3k $20.3m | Reduced -52.2k |
| Erste Asset Management GmbH 0.17% of their portfolio | 210.0k $18.5m | Reduced -40.0k |
| Ensign Peak Advisors, Inc 0.03% of their portfolio | 202.5k $18.7m | Added +68.5k |
| NEW YORK STATE COMMON RETIREMENT FUND 0.03% of their portfolio | 201.1k $18.6m | Reduced -16.5k |
| Logos Global Management LP 0.95% of their portfolio | 200.0k $18.5m | Reduced -25.0k |
| Russell Investments Group, Ltd. 0.02% of their portfolio | 197.1k $18.2m | Reduced -12.1k |
| Atle Fund Management AB 3.03% of their portfolio | 195.8k $9.4m | Added +106.1k |
| Handelsbanken Fonder AB 0.06% of their portfolio | 194.0k $17.9m | Reduced -19.5k |
| SEGALL BRYANT & HAMILL, LLC 0.23% of their portfolio | 175.9k $16.2m | Reduced -9.1k |
| D. E. Shaw & Co., Inc. 0.01% of their portfolio | 167.5k $15.5m | Reduced -780.7k |
| Legal & General Group Plc 0.00% of their portfolio | 153.9k $14.2m | Reduced -14.5k |
| CITIGROUP INC 0.01% of their portfolio | 153.5k $14.2m | Added +7.5k |
| FIRST TRUST ADVISORS LP 0.01% of their portfolio | 151.3k $14.0m | Added +13.6k |
| Voleon Capital Management LP 0.30% of their portfolio | 150.5k $13.9m | Reduced -22.6k |
| RICE HALL JAMES & ASSOCIATES, LLC 0.76% of their portfolio | 147.0k $13.6m | Reduced -17.4k |
| PDT Partners, LLC 0.79% of their portfolio | 145.4k $13.4m | Unchanged |
| Nicholas Investment Partners, LP 0.88% of their portfolio | 131.3k $12.1m | Reduced -82.1k |
| PANAGORA ASSET MANAGEMENT INC 0.04% of their portfolio | 129.1k $11.9m | New |
| Highlander Partners, L.P. 4.45% of their portfolio | 123.0k $11.4m | Unchanged |
| ESSEX INVESTMENT MANAGEMENT CO LLC 1.58% of their portfolio | 108.3k $10.0m | Reduced -3.0k |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC 0.04% of their portfolio | 104.1k $9.6m | Reduced -193.9k |
| VICTORY CAPITAL MANAGEMENT INC 0.01% of their portfolio | 95.6k $8.8m | Added +23.4k |
| Hennion & Walsh Asset Management, Inc. 0.29% of their portfolio | 93.6k $8.6m | Reduced -4.7k |
| Fisher Asset Management, LLC 0.00% of their portfolio | 93.1k $8.6m | Added +79.0k |
| Rhenman & Partners Asset Management AB 1.06% of their portfolio | 92.6k $8.6m | Reduced -13.7k |
| JPMORGAN CHASE & CO 0.00% of their portfolio | 90.7k $8.0m | Reduced -6.7k |
| ExodusPoint Capital Management, LP 0.08% of their portfolio | 87.4k $8.1m | New |
| SEI INVESTMENTS CO 0.01% of their portfolio | 81.1k $7.5m | Added +35.0k |
| SILVERCREST ASSET MANAGEMENT GROUP LLC 0.05% of their portfolio | 81.0k $7.5m | Reduced -9.1k |
| NEUBERGER BERMAN GROUP LLC 0.01% of their portfolio | 80.5k $7.4m | New |
| Swiss National Bank 0.00% of their portfolio | 74.3k $6.9m | Unchanged |
| PICTON MAHONEY ASSET MANAGEMENT 0.07% of their portfolio | 74.1k $6.8m | Added +72.7k |
| VOYA INVESTMENT MANAGEMENT LLC 0.01% of their portfolio | 68.8k $6.4m | Added +1.1k |