X4 Pharmaceuticals, Inc. has 29 Schedule 13D or 13G filings on record since 2025-07-18. 12 holders' latest filing reports 5% or more of common stock, $0.001 par value per share. Each figure below is the holder's own, as filed, with the filing linked.
Holders
| Holder | Percent | Shares | Latest | Event date |
|---|---|---|---|---|
| Morgan Stanley | 10.2% | 8,884,338 | SCHEDULE 13G/A, 2026-03-06 | 2026-02-28 |
| Coastlands Capital LP | 9.99% | 2,491,638 | SCHEDULE 13G, 2025-10-03 | 2025-10-03 |
| Empery Asset Management, LP | 9.99% | 9,043,894 | SCHEDULE 13G/A, 2026-01-15 | 2025-12-31 |
| Fmr LLC | 9.7% | 8,499,100 | SCHEDULE 13G/A, 2026-02-05 | 2025-10-31 |
| Deep Track Capital, LP | 8.33% | 8,040,894 | SCHEDULE 13G/A, 2026-08-14 | 2026-06-30 |
| Perceptive Advisors LLC | 8.1% | 8,085,006 | SCHEDULE 13G/A, 2026-08-14 | 2026-06-30 |
| BCLS II Equity Opportunities, LP | 7.43% | 7,047,216 | SCHEDULE 13G/A, 2026-02-17 | 2025-12-31 |
| Saturn V Capital Management LP | 7.36% | 6,433,481 | SCHEDULE 13G, 2026-02-17 | 2025-10-24 |
| Growth Equity Opportunities 18 VGE, LLC | 6.2% | 5,057,610 | SCHEDULE 13D/A, 2025-10-29 | 2025-10-27 |
| BlackRock, Inc. | 5.9% | 5,529,573 | SCHEDULE 13G, 2026-07-30 | 2026-06-30 |
| Trails Edge Capital Partners, LP | 5.8% | 5,227,222 | SCHEDULE 13G/A, 2026-02-17 | 2025-12-31 |
| Venrock Healthcare Capital Partners III, L.P. | 5.6% | 5,555,047 | SCHEDULE 13G, 2026-09-21 | 2026-09-14 |
| Bvf Partners L P | 3.9% | 3,411,993 | SCHEDULE 13G/A, 2026-02-17 | 2025-12-31 |
| Nantahala Capital Management, LLC | 2.8% | 2,449,468 | SCHEDULE 13G/A, 2026-02-13 | 2025-12-31 |
| Orbimed Advisors LLC | 1.7% | 134,947 | SCHEDULE 13G/A, 2025-08-14 | 2025-06-30 |
Purpose of Transaction (Item 4)
Growth Equity Opportunities 18 VGE, LLC
GEO acquired the GEO Shares for investment purposes. Information with respect to the Offering set forth in Item 3 above is incorporated herein by reference to the extent responsive to this Item 4. Subject to the foregoing, depending on market conditions, its continuing evaluation of the business and prospects of the Issuer and other factors, GEO and 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 corporate transaction, such as a merger, reorganization or liquidation, involving the Issuer or any of its subsidiaries; (c) A sale or transfer of a material amount of assets of the Issuer or any of its subsidiaries; (d) Any change in the present board of directors or management of the Issuer, including any plans or proposals to change the number or term of directors or to fill any existing vacancies on the board; (e) Any material change in the present capitalization or dividend policy of the Issuer; (f) Any other material change in the Issuer's business or corporate structure; (g) Changes in the Issuer's charter, bylaws or instruments corresponding thereto or other actions which may impede the acquisition of control of the Issuer by any person; (h) Causing a class of securities of the …The first part of Item 4 of the SCHEDULE 13D/A filed 2025-10-29; the filing has the rest
Timeline
| Filed | Holder | Percent | Filing |
|---|---|---|---|
| 2025-07-18 | BlackRock, Inc. | 3% | SCHEDULE 13G/A |
| 2025-08-13 | Bain Capital Life Sciences Fund, L.P. | 9.99% | SCHEDULE 13D |
| 2025-08-14 | Orbimed Advisors LLC | 1.7% | SCHEDULE 13G/A |
| 2025-08-15 | Growth Equity Opportunities 18 VGE, LLC | 9.99% | SCHEDULE 13D/A |
| 2025-08-18 | Coastlands Capital LP | 9.99% | SCHEDULE 13D |
| 2025-08-18 | Trails Edge Capital Partners, LP | 9.9% | SCHEDULE 13G |
| 2025-08-19 | Deep Track Capital, LP | 9.99% | SCHEDULE 13G |
| 2025-08-20 | Bvf Partners L P | 9.9% | SCHEDULE 13G |
| 2025-09-15 | Bain Capital Life Sciences Fund, L.P. | 9.99% | SCHEDULE 13G |
| 2025-10-03 | Coastlands Capital LP | 9.99% | SCHEDULE 13G |
| 2025-10-21 | Empery Asset Management, LP | 9.99% | SCHEDULE 13G |
| 2025-10-29 | Growth Equity Opportunities 18 VGE, LLC | 6.2% | SCHEDULE 13D/A |
| 2025-11-03 | Perceptive Advisors LLC | 7.6% | SCHEDULE 13G |
| 2025-11-07 | Fmr LLC | 14.8% | SCHEDULE 13G |
| 2025-11-14 | Nantahala Capital Management, LLC | 9.99% | SCHEDULE 13G |
| 2026-01-15 | Empery Asset Management, LP | 9.99% | SCHEDULE 13G/A |
| 2026-02-05 | Fmr LLC | 9.7% | SCHEDULE 13G/A |
| 2026-02-12 | Morgan Stanley | 9.4% | SCHEDULE 13G |
| 2026-02-13 | Nantahala Capital Management, LLC | 2.8% | SCHEDULE 13G/A |
| 2026-02-17 | Bvf Partners L P | 3.9% | SCHEDULE 13G/A |
| 2026-02-17 | Saturn V Capital Management LP | 7.36% | SCHEDULE 13G |
| 2026-02-17 | BCLS II Equity Opportunities, LP | 7.43% | SCHEDULE 13G/A |
| 2026-02-17 | Trails Edge Capital Partners, LP | 5.8% | SCHEDULE 13G/A |
| 2026-03-06 | Morgan Stanley | 10.2% | SCHEDULE 13G/A |
| 2026-05-15 | Perceptive Advisors LLC | 7.3% | SCHEDULE 13G/A |
| 2026-07-30 | BlackRock, Inc. | 5.9% | SCHEDULE 13G |
| 2026-08-14 | Deep Track Capital, LP | 8.33% | SCHEDULE 13G/A |
| 2026-08-14 | Perceptive Advisors LLC | 8.1% | SCHEDULE 13G/A |
| 2026-09-21 | Venrock Healthcare Capital Partners III, L.P. | 5.6% | SCHEDULE 13G |
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Where this comes from
Anyone who comes to own more than 5% of a class of a listed company's voting shares has to tell the SEC. A holder who may seek to change or influence the company files Schedule 13D, and has to say in Item 4, "Purpose of Transaction", what it intends to do. A holder with no such intent, such as many index and passive funds, may file the shorter Schedule 13G. Both are amended when the stake changes, including when it falls below 5%.
Every row here is one of those filings, linked to the filing itself. Percentages and share counts are exactly as the holder filed them, for the holder the filing names; an amendment showing a lower figure is shown as filed. Item 4 text is quoted word for word. Where a 13D's Item 4 contains a sentence stating a definite intent to influence the company, that sentence is marked and quoted; the page does not describe the holder or its motives beyond the words it filed. Nothing here is investment advice.
