person · Reporting owner
Fairmount Healthcare Co-Invest IV L.P.
Disclosed activity across 1 company
Sign in to followReported relationships
Latest disclosed role at each company.
| Company | Last reported as | Report date | Published |
|---|---|---|---|
| Jade Biosciences, Inc.JBIO · Entity 4757 | Director · 10% owner | June 09, 2026 | June 11, 2026 |
Disclosed balances
About these balances
Latest available filing per company, not a reconstructed current portfolio. Matching sequences show the last reported balance with all source rows expandable; grouping alone does not establish account ownership. Do not add unresolved positions together. Filings may omit unchanged positions, and amendments may correct only part of an older disclosure. Jointly reported shares are not necessarily this owner's personal holdings.
Jade Biosciences, Inc.
Report date June 09, 2026 · Filed June 11, 2026
Jointly reported with Fairmount Funds Management LLC, Fairmount Healthcare Fund II L.P., Kiselak Tomas, Harwin Peter Evan
| Security / award | Ownership account | Disclosed shares / units | Disclosure context |
|---|---|---|---|
| Stock Option (Right to Buy)SEC Table II · derivative / convertible security · Conversion / exercise price $15.22 · Expires 2036-06-08 | Direct | 34,843 |
Reported balance
After 2026-06-09 transaction · row 1
Instrument identity requires review; Table II rows are not merged.
1 source rowRow 1 · 2026-06-09 · Grant · Acquired 34,843 · Balance 34,843 F1: This option represents a right to purchase shares of the Issuer's common stock, which vests in full on the earlier of (i) June 9, 2027 or (ii) the date of the next annual meeting of the Issuer's stockholders, in each case, subject to Tomas Kiselak's continued service to the Issuer. F2: Fairmount Funds Management LLC ("Fairmount") is the investment manager for Fairmount Healthcare Fund II LP ("Fund II") and Fairmount Healthcare Co-Invest IV L.P. ("Co-Invest"). Peter Harwin and Tomas Kiselak are the managers of Fairmount. Under Mr. Kiselak's arrangement with Fairmount, Mr. Kiselak holds the option for one or more investment vehicles managed by Fairmount (each, a "Fairmount Fund"). Mr. Kiselak is obligated to turn over to Fairmount any net cash or stock received from the option for the benefit of such Fairmount Fund. Fairmount, Mr. Harwin, and Mr. Kiselak disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein. |
Filing footnotes · ownership attribution and instrument terms
F1: This option represents a right to purchase shares of the Issuer's common stock, which vests in full on the earlier of (i) June 9, 2027 or (ii) the date of the next annual meeting of the Issuer's stockholders, in each case, subject to Tomas Kiselak's continued service to the Issuer.
F2: Fairmount Funds Management LLC ("Fairmount") is the investment manager for Fairmount Healthcare Fund II LP ("Fund II") and Fairmount Healthcare Co-Invest IV L.P. ("Co-Invest"). Peter Harwin and Tomas Kiselak are the managers of Fairmount. Under Mr. Kiselak's arrangement with Fairmount, Mr. Kiselak holds the option for one or more investment vehicles managed by Fairmount (each, a "Fairmount Fund"). Mr. Kiselak is obligated to turn over to Fairmount any net cash or stock received from the option for the benefit of such Fairmount Fund. Fairmount, Mr. Harwin, and Mr. Kiselak disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein.
Transaction history
JSON APIPurchases/sales include open-market and private transactions. Plan disclosure applies to the filing; individual rows may differ. “Not disclosed” is not “unplanned.”
The cutoff filters transaction history only. Company summaries and owner relationships show the latest available disclosures. Parser corrections can improve historical records.
| Transaction date | Company | Activity / security | Shares / units | Reported price | Reported value | Details |
|---|---|---|---|---|---|---|
| June 09, 2026 Filed Jun 11, 2026 20:37 UTC | Jade Biosciences, Inc. JBIO · Entity 4757 | GrantStock Option (Right to Buy) · Derivative | 34,843 | $0.00 Strike: $15.22 | $0.00 |
DisclosureSEC source: 0001193125-26-267706 · ownership.xml · derivative · entry 1 Fairmount Funds Management LLC · CIK 0001802528 · Director · 10% owner Fairmount Healthcare Fund II L.P. · CIK 0001769651 · Director · 10% owner Fairmount Healthcare Co-Invest IV L.P. · CIK 0002042283 · Director · 10% owner Kiselak Tomas · CIK 0001830177 · Director · 10% owner Harwin Peter Evan · CIK 0001663607 · Director · 10% owner Joint disclosure: these amounts are not allocated separately to each reporting owner. 10b5-1 filing: No plan indicated Ownership: Direct Disclosed balance after: 34,843 Underlying: Common Stock · 34,843 shares Expires 2036-06-08 F1 · derivative.exercise_date: This option represents a right to purchase shares of the Issuer's common stock, which vests in full on the earlier of (i) June 9, 2027 or (ii) the date of the next annual meeting of the Issuer's stockholders, in each case, subject to Tomas Kiselak's continued service to the Issuer. F2 · ownership.direct: Fairmount Funds Management LLC ("Fairmount") is the investment manager for Fairmount Healthcare Fund II LP ("Fund II") and Fairmount Healthcare Co-Invest IV L.P. ("Co-Invest"). Peter Harwin and Tomas Kiselak are the managers of Fairmount. Under Mr. Kiselak's arrangement with Fairmount, Mr. Kiselak holds the option for one or more investment vehicles managed by Fairmount (each, a "Fairmount Fund"). Mr. Kiselak is obligated to turn over to Fairmount any net cash or stock received from the option for the benefit of such Fairmount Fund. Fairmount, Mr. Harwin, and Mr. Kiselak disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein. Read SEC document |
| October 06, 2025 Filed Oct 8, 2025 20:15 UTC | Jade Biosciences, Inc. JBIO · Entity 4757 | GrantPre-Funded Warrant (Right to Buy) · Derivative | 855,047 | $9.14 Strike: $0.00 | $7,815,044.08 |
DisclosureSEC source: 0001104659-25-097921 · tm2528311-1_4seq1.xml · derivative · entry 3 Fairmount Funds Management LLC · CIK 0001802528 · Director · 10% owner Fairmount Healthcare Fund II L.P. · CIK 0001769651 · Director · 10% owner Fairmount Healthcare Co-Invest IV L.P. · CIK 0002042283 · Director · 10% owner Kiselak Tomas · CIK 0001830177 · Director · 10% owner Harwin Peter Evan · CIK 0001663607 · Director · 10% owner Joint disclosure: these amounts are not allocated separately to each reporting owner. 10b5-1 filing: No plan indicated Ownership: Indirect · By Fairmount Healthcare Fund II L.P. Disclosed balance after: 855,047 Underlying: Common Stock · 855,047 shares Expires not disclosed F1 · kind: The shares of Common Stock and Pre-Funded Warrants were purchased from the Issuer in a private placement, which transaction is exempt from Section 16(b) in accordance with Rule 16b-3(d)(1) promulgated under the Securities Exchange Act of 1934, as amended. F3 · derivative.exercise_date: The Pre-Funded Warrants have no expiration date and are exercisable at any time after the date of issuance. A holder of Pre-Funded Warrants may not exercise the Pre-Funded Warrant if the holder, together with its affiliates, would beneficially own more than 9.99% of the number of outstanding shares of common stock of the Issuer immediately after giving effect to such exercise. F3 · derivative.expiration_date: The Pre-Funded Warrants have no expiration date and are exercisable at any time after the date of issuance. A holder of Pre-Funded Warrants may not exercise the Pre-Funded Warrant if the holder, together with its affiliates, would beneficially own more than 9.99% of the number of outstanding shares of common stock of the Issuer immediately after giving effect to such exercise. F2 · ownership.nature: Fairmount Funds Management LLC ("Fairmount") is the investment manager for Fairmount Healthcare Fund II L.P. and Fairmount Healthcare Co-Invest IV L.P. The managers of Fairmount are Peter Harwin and Tomas Kiselak. Fairmount, Mr. Harwin, and Mr. Kiselak disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein. Read SEC document |
| October 06, 2025 Filed Oct 8, 2025 20:15 UTC | Jade Biosciences, Inc. JBIO · Entity 4757 | GrantCommon Stock | 1,333,126 | $9.14 | $12,184,771.64 |
DisclosureSEC source: 0001104659-25-097921 · tm2528311-1_4seq1.xml · nonDerivative · entry 1 Fairmount Funds Management LLC · CIK 0001802528 · Director · 10% owner Fairmount Healthcare Fund II L.P. · CIK 0001769651 · Director · 10% owner Fairmount Healthcare Co-Invest IV L.P. · CIK 0002042283 · Director · 10% owner Kiselak Tomas · CIK 0001830177 · Director · 10% owner Harwin Peter Evan · CIK 0001663607 · Director · 10% owner Joint disclosure: these amounts are not allocated separately to each reporting owner. 10b5-1 filing: No plan indicated Ownership: Indirect · By Fairmount Healthcare Fund II L.P. Disclosed balance after: 1,897,677 F1 · kind: The shares of Common Stock and Pre-Funded Warrants were purchased from the Issuer in a private placement, which transaction is exempt from Section 16(b) in accordance with Rule 16b-3(d)(1) promulgated under the Securities Exchange Act of 1934, as amended. F2 · ownership.nature: Fairmount Funds Management LLC ("Fairmount") is the investment manager for Fairmount Healthcare Fund II L.P. and Fairmount Healthcare Co-Invest IV L.P. The managers of Fairmount are Peter Harwin and Tomas Kiselak. Fairmount, Mr. Harwin, and Mr. Kiselak disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein. Read SEC document |
Value uses the disclosed total when available, otherwise shares × reported transaction price. It is not an estimate of exercise cash cost or investment performance.