Immuneering Corporation (IMRX) Ownership
IMRX ownership summary
as of October 18, 2026- Institutions
- 55.5% of shares outstanding
- Insiders
- 13.83% of shares outstanding
- Shares outstanding
- 64.7M
- Float
- 49.2M shares available to trade
- Short interest
- 31.56% 15.5M shares short
- Days to cover
- 22.22 short interest down 0.4% vs prior month
- Institutions 55.47%
- Insiders 13.83%
- Other investors 30.70%
IMRX top institutional holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | FMR Inc | 15.00% | 9.7M | $34.8M | +6,672 (+0.1%) | June 30, 2026 |
| 2 | BlackRock Inc | 6.76% | 4.4M | $15.7M | +2.9M (+190.2%) | June 30, 2026 |
| 3 | Sanofi | 4.19% | 2.7M | $9.7M | — | June 30, 2026 |
| 4 | Vanguard Capital Management, LLC | 3.53% | 2.3M | $8.2M | −1,907 (−0.1%) | June 30, 2026 |
| 5 | T. Rowe Price Associates, Inc. | 2.99% | 1.9M | $7.0M | +106,888 (+5.8%) | June 30, 2026 |
| 6 | Geode Capital Management, LLC | 2.12% | 1.4M | $4.9M | +732,806 (+114.9%) | June 30, 2026 |
| 7 | State Street Corp | 1.55% | 1.0M | $3.6M | +733,475 (+273.2%) | June 30, 2026 |
| 8 | DCF Advisers, LLC | 1.22% | 790K | $2.8M | +648,538 (+458.5%) | June 30, 2026 |
| 9 | Marshall Wace Asset Management Ltd | 1.13% | 732K | $2.6M | −1.3M (−63.3%) | June 30, 2026 |
| 10 | Connor Clark & Lunn Inv Mgmt Ltd | 0.93% | 601K | $2.2M | +200,892 (+50.2%) | June 30, 2026 |
| 11 | Alethea Capital Management, LLC | 0.73% | 473K | $1.7M | +450,000 (+1,962.1%) | June 30, 2026 |
| 12 | Summit Financial LLC | 0.70% | 452K | $1.6M | +75,515 (+20.0%) | June 30, 2026 |
| 13 | UBS Group AG | 0.69% | 449K | $1.6M | +72,573 (+19.3%) | June 30, 2026 |
| 14 | Nuveen, LLC | 0.68% | 438K | $1.6M | +438,362 (0.0%) | June 30, 2026 |
| 15 | Northern Trust Corp | 0.68% | 437K | $1.6M | +319,326 (+271.4%) | June 30, 2026 |
| 16 | Easterly Investment Partners. | 0.64% | 414K | $1.5M | +404,000 (+4,040.0%) | June 30, 2026 |
| 17 | Citadel Advisors Llc | 0.60% | 386K | $1.4M | −60,867 (−13.6%) | June 30, 2026 |
| 18 | Vanguard Fiduciary Trust Co | 0.56% | 361K | $1.3M | +38,726 (+12.0%) | June 30, 2026 |
| 19 | Vanguard Portfolio Management, LLC | 0.56% | 359K | $1.3M | +359,085 (0.0%) | June 30, 2026 |
| 20 | GSA Capital Partners LLP | 0.53% | 343K | $1.2M | +266,551 (+347.3%) | June 30, 2026 |
Value at the latest close. Change = shares bought or sold in the latest quarterly filing (13F). In the top 20, 16 holders added 7.7M shares and 3 cut 1.3M.
IMRX top mutual fund and ETF holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | HBM Healthcare Investments AG Ord | 5.64% | 3.6M | $13.1M | — | June 30, 2026 |
| 2 | Fidelity Growth Company Fund | 4.54% | 2.9M | $10.6M | — | August 31, 2026 |
| 3 | Vanguard MStar Total Stk Mkt Idx Invest | 2.51% | 1.6M | $5.8M | — | August 31, 2026 |
| 4 | iShares Russell 2000 ETF | 2.20% | 1.4M | $5.1M | −16,384 (−1.1%) | September 30, 2026 |
| 5 | Fidelity Select Biotechnology | 1.69% | 1.1M | $3.9M | — | August 31, 2026 |
| 6 | Fidelity Growth Company K6 | 1.29% | 832K | $3.0M | — | August 31, 2026 |
| 7 | Fidelity Series Growth Company | 1.11% | 720K | $2.6M | — | August 31, 2026 |
| 8 | Fidelity Small Cap Index | 0.90% | 584K | $2.1M | +1,625 (+0.3%) | July 31, 2026 |
| 9 | iShares Russell 2000 Value ETF | 0.82% | 531K | $1.9M | +804 (+0.2%) | September 30, 2026 |
| 10 | iShares Biotechnology ETF | 0.69% | 449K | $1.6M | −3,400 (−0.8%) | September 30, 2026 |
| 11 | Nuveen Equity Index R6 | 0.51% | 330K | $1.2M | — | August 31, 2026 |
| 12 | Vanguard Russell 2000 ETF | 0.47% | 307K | $1.1M | +6,120 (+2.0%) | August 31, 2026 |
| 13 | Fidelity Extended Market Index | 0.43% | 276K | $991,210 | +6,757 (+2.5%) | August 31, 2026 |
| 14 | iShares Micro-Cap ETF | 0.28% | 178K | $640,072 | −1,230 (−0.7%) | September 30, 2026 |
| 15 | CREF Total Global Stock Account R3 | 0.27% | 178K | $637,979 | +141,190 (+386.6%) | July 31, 2026 |
| 16 | Schwab Small Cap Index | 0.20% | 131K | $468,700 | — | August 31, 2026 |
| 17 | Stt Strt SPDR® Russell2000 US SmCapETF | 0.18% | 118K | $422,715 | +5,632 (+5.0%) | August 31, 2026 |
| 18 | Fidelity Total Market Index | 0.16% | 103K | $369,709 | — | August 31, 2026 |
| 19 | iShares Russell 2000 Small-Cap Idx Instl | 0.15% | 100K | $359,819 | — | August 31, 2026 |
| 20 | ALPS Medical Breakthroughs ETF | 0.13% | 85K | $305,541 | — | September 30, 2026 |
Funds report holdings monthly or quarterly; dates differ by fund.
IMRX insider transactions
latest 20| Date | Name | Transaction | Price | Shares | Value |
|---|---|---|---|---|---|
| 2026-01-16 | Harold Eugene Brakewood | Buy | $4.76 | 5,250 | $24,990 |
| 2026-01-15 | Brett Matthew Hall | Buy | $4.57 | 2,298 | $10,502 |
| 2026-01-15 | Thomas J Schall | Buy | $4.67 | 21,645 | $101,082 |
| 2026-01-13 | Leah R Neufeld | Buy | $4.15 | 2,626 | $10,898 |
| 2026-01-12 | Peter Feinberg | Buy | $4.35 | 20,000 | $87,000 |
| 2025-10-03 | Peter Feinberg | Buy | $6.67 | 7,500 | $50,025 |
| 2025-10-01 | Leah R Neufeld | Buy | $6.38 | 800 | $5,104 |
| 2025-09-30 | Peter Feinberg | Buy | $7.03 | 7,500 | $52,725 |
| 2025-09-29 | Peter Feinberg | Buy | $7.18 | 5,000 | $35,900 |
| 2025-07-02 | Diana Hausman | Buy | $3.60 | 2,500 | $9,000 |
| 2025-07-02 | Leah R Neufeld | Buy | $3.57 | 700 | $2,499 |
| 2025-07-02 | Diana Hausman | Buy | $3.62 | 3,000 | $10,860 |
| 2025-07-02 | Benjamin J Zeskind | Buy | $3.53 | 7,015 | $24,763 |
| 2025-07-01 | Benjamin J Zeskind | Buy | $3.38 | 2,985 | $10,089 |
| 2025-06-27 | Thomas J Schall | Buy | $3.66 | 9,500 | $34,770 |
| 2025-06-23 | Brett Matthew Hall | Buy | $2.43 | 6,007 | $14,597 |
| 2025-06-20 | Brett Matthew Hall | Buy | $2.70 | 7,415 | $20,020 |
| 2025-06-20 | Harold Eugene Brakewood | Buy | $2.53 | 1,900 | $4,807 |
| 2025-06-18 | Benjamin J Zeskind | Buy | $2.39 | 21,000 | $50,190 |
| 2025-06-18 | Peter Feinberg | Buy | $2.53 | 25,000 | $63,250 |
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.
IMRX shares outstanding
Year-end shares outstanding, adjusted for splits.
Who owns IMRX
Institutional investors own 55.5% of Immuneering's shares and insiders 13.83%. The largest holder is FMR Inc with 15.00% of the shares (9.7M), as of June 30, 2026. Among the top 20 institutions, 16 added shares and 3 reduced their stake in the latest filings. Short interest is 31.56% of the float, or 22.22 days of average trading volume. The share count rose 378.0% since 2020.
Related: IMRX analyst forecast, IMRX key metrics. See the IMRX stock overview for the latest quote and news.
IMRX ownership FAQ
Who owns the most Immuneering stock?
The largest shareholders of Immuneering are FMR Inc (15.00%), BlackRock Inc (6.76%), Sanofi (4.19%), Vanguard Capital Management, LLC (3.53%), T. Rowe Price Associates, Inc. (2.99%).
What percentage of Immuneering is owned by institutions?
Institutions hold 55.5% of Immuneering's shares outstanding; insiders hold 13.83%.
Which funds own Immuneering?
The largest fund holders of Immuneering are HBM Healthcare Investments AG Ord (5.64%), Fidelity Growth Company Fund (4.54%), Vanguard MStar Total Stk Mkt Idx Invest (2.51%), iShares Russell 2000 ETF (2.20%), Fidelity Select Biotechnology (1.69%).
What is Immuneering's short interest?
15.5M shares of Immuneering were sold short, 31.56% of the float; at the average daily volume it would take 22.22 days to cover.
Are insiders buying or selling Immuneering?
Of the latest 20 reported insider transactions in Immuneering (since June 18, 2025), 20 were purchases and 0 were sales.
How many shares of Immuneering are outstanding?
Immuneering has 64.7M shares outstanding, of which 49.2M are in the public float.