Related Party Transactions	9 Months Ended
Sep. 30, 2025
Related Party Transactions [Abstract]
Related Party Transactions	Note 9. Related Party Transactions Research Collaboration Agreement with TCGFB, Inc. In October 2024, the Company entered into a strategic research collaboration with a privately-held company, TCGFB, Inc., or TCGFB, to discover antibody therapeutics targeting transforming growth factor beta, or TGF-β, for the potential treatment of patients with idiopathic pulmonary fibrosis, or the TCGFB Collaboration. TCGFB will own all TGF-β product related intellectual property. Under the terms of the agreement, the Company provides antibody discovery services for a period of up to two years and delivers a non-exclusive license as necessary for continued research. TCGFB may terminate this agreement at any time upon prior written notice. Upon termination, TCGFB shall pay to the Company all sums owed for services completed up to the effective termination date. In exchange for the Company’s research services, TCGFB pays a fixed monthly service fee up to $6.0 million in the aggregate, plus any third-party costs, and issued the Company a warrant exercisable for up to 3.4 million shares of TCGFB common stock at an exercise price of $0.0001 per share. 2.4 million shares of the warrant vest monthly over 2 years, 0.5 million shares vest on the 18-month anniversary, and 0.5 million shares vest on the 24-month anniversary. TCGFB was founded and is controlled by entities affiliated with The Column Group. The agreement constitutes a related party transaction because entities affiliated with The Column Group hold more than 5% of the Company’s common stock and Dr. Kutzkey, a member of the Company’s board of directors, serves as Managing Partner of The Column Group. While TCGFB is not a customer and the service being provided is consistent with the Company's ordinary activities, the Company determined that the TCGFB Collaboration is in the scope of ASC 606 by analogy. The Company evaluated the promised goods and services and determined that the service to TCGFB and the potential grant of the non-exclusive license represented one combined performance obligation for discovery antibody therapeutics targeting TGF-β. The transaction price was determined to be the fixed monthly service fee plus variable consideration related to the warrant. Revenue is recognized over time for the combined performance obligation using the input method. The warrant received does not meet the definition of a derivative and is accounted for as an equity investment under ASC 321. The fair value of the warrant at inception was determined to be $2.6 million in October 2024. The warrant is recognized as warrant asset once the vesting restrictions are lifted. During the three and nine months ended September 30, 2025, the Company recognized $1.0 million and $2.9 million as research service revenue – related party for the services rendered, consisting of the fixed cash consideration of $0.8 million and $2.3 million and the variable noncash consideration of $0.2 million and $0.6 million, respectively. In October 2025, the Company received a notice from TCGFB that TCGFB has elected to terminate the TCGFB Collaboration. Please see Note 13. 2024 Private Placement As described in Note 8, the Company entered into a securities purchase agreement with investors and certain members of management in April 2024, whereby the Company issued and sold to members of management 2,948 shares of common stock, at a purchase price of $16.96 per share for aggregate gross proceeds of $0.1 million. The purchase price per share of common stock includes $1.25 for the following 2024 PIPE Warrants: • Series A common stock warrants to purchase up to 2,948 shares of common stock with an exercise price of $16.96 per share. The exercise price per share of these warrants was reduced to $12.45 per share in March 2025. Please see Note 3. • Series B common stock warrants to purchase up to 3,206 shares of common stock with an exercise price of $15.71 per share. The exercise price per share of these warrants was reduced to $12.45 per share in March 2025. Please see Note 3. • Series C common stock warrants to purchase up to 11,424 shares of common stock with an exercise purchase price of $16.00 per share. These warrants were cancelled in March 2025. Please see Note 3. • Series D common stock warrants to purchase up to 11,424 shares of common stock with an exercise price of $16.00 per share. These warrants were cancelled in March 2025. Please see Note 3. The terms of the warrants held by management are the same as those held by the investors, except for the purchase price and exercise price of warrants. Please see Note 10 for the terms of the warrants. Sublease In April 2024, the Company entered into a related party transaction with Nura Bio, Inc., or Nura Bio, to sublease approximately 6,102 square feet of the Company’s office and laboratory space. The sublease term was initially on a month-to-month basis and the monthly base rent is approximately $35,000, escalating at 3% per annum. In July 2025, the Company and Nura Bio executed a sublease extension agreement effective May 2025, to extend the lease term for an additional 12 months until May 2026. Nura Bio is also responsible for its share of real estate taxes, utilities and other operating expenses applicable to the subleased space. During the three and nine months ended September 30, 2025 and 2024, the Company recognized sublease income of $0.2 million, $0.5 million, $0.2 million and $0.3 million, respectively, as reductions to operating expenses. Tim Kutzkey, Ph.D., a member of the Company’s board of directors, serves as the chairman of the board of directors of Nura Bio. Dr. Kutzkey also serves as Managing Partner of The Column Group, LLC, which is the general partner of certain limited partnerships which are significant stockholders of Nura Bio. The Column Group holds more than 5% of the Company’s common stock. Therefore, the agreement constitutes a related party transaction.

Related Party Transactions

9 Months Ended

Sep. 30, 2025

Research Collaboration Agreement with TCGFB, Inc.

In October 2024, the Company entered into a strategic research collaboration with a privately-held company, TCGFB, Inc., or TCGFB, to discover antibody therapeutics targeting transforming growth factor beta, or TGF-β, for the potential treatment of patients with idiopathic pulmonary fibrosis, or the TCGFB Collaboration. TCGFB will own all TGF-β product related intellectual property. Under the terms of the agreement, the Company provides antibody discovery services for a period of up to two years and delivers a non-exclusive license as necessary for continued research. TCGFB may terminate this agreement at any time upon prior written notice. Upon termination, TCGFB shall pay to the Company all sums owed for services completed up to the effective termination date. In exchange for the Company’s research services, TCGFB pays a fixed monthly service fee up to $6.0 million in the aggregate, plus any third-party costs, and issued the Company a warrant exercisable for up to 3.4 million shares of TCGFB common stock at an exercise price of $0.0001 per share. 2.4 million shares of the warrant vest monthly over 2 years, 0.5 million shares vest on the 18-month anniversary, and 0.5 million shares vest on the 24-month anniversary. TCGFB was founded and is controlled by entities affiliated with The Column Group. The agreement constitutes a related party transaction because entities affiliated with The Column Group hold more than 5% of the Company’s common stock and Dr. Kutzkey, a member of the Company’s board of directors, serves as Managing Partner of The Column Group.

While TCGFB is not a customer and the service being provided is consistent with the Company's ordinary activities, the Company determined that the TCGFB Collaboration is in the scope of ASC 606 by analogy. The Company evaluated the promised goods and services and determined that the service to TCGFB and the potential grant of the non-exclusive license represented one combined performance obligation for discovery antibody therapeutics targeting TGF-β. The transaction price was determined to be the fixed

monthly service fee plus variable consideration related to the warrant. Revenue is recognized over time for the combined performance obligation using the input method.

The warrant received does not meet the definition of a derivative and is accounted for as an equity investment under ASC 321. The fair value of the warrant at inception was determined to be $2.6 million in October 2024. The warrant is recognized as warrant asset once the vesting restrictions are lifted. During the three and nine months ended September 30, 2025, the Company recognized $1.0 million and $2.9 million as research service revenue – related party for the services rendered, consisting of the fixed cash consideration of $0.8 million and $2.3 million and the variable noncash consideration of $0.2 million and $0.6 million, respectively.

In October 2025, the Company received a notice from TCGFB that TCGFB has elected to terminate the TCGFB Collaboration. Please see Note 13.

2024 Private Placement

As described in Note 8, the Company entered into a securities purchase agreement with investors and certain members of management in April 2024, whereby the Company issued and sold to members of management 2,948 shares of common stock, at a purchase price of $16.96 per share for aggregate gross proceeds of $0.1 million. The purchase price per share of common stock includes $1.25 for the following 2024 PIPE Warrants:

•

Series A common stock warrants to purchase up to 2,948 shares of common stock with an exercise price of $16.96 per share. The exercise price per share of these warrants was reduced to $12.45 per share in March 2025. Please see Note 3.

•

Series B common stock warrants to purchase up to 3,206 shares of common stock with an exercise price of $15.71 per share. The exercise price per share of these warrants was reduced to $12.45 per share in March 2025. Please see Note 3.

•

Series C common stock warrants to purchase up to 11,424 shares of common stock with an exercise purchase price of $16.00 per share. These warrants were cancelled in March 2025. Please see Note 3.

•

Series D common stock warrants to purchase up to 11,424 shares of common stock with an exercise price of $16.00 per share. These warrants were cancelled in March 2025. Please see Note 3.

The terms of the warrants held by management are the same as those held by the investors, except for the purchase price and exercise price of warrants. Please see Note 10 for the terms of the warrants.

Sublease

In April 2024, the Company entered into a related party transaction with Nura Bio, Inc., or Nura Bio, to sublease approximately 6,102 square feet of the Company’s office and laboratory space. The sublease term was initially on a month-to-month basis and the monthly base rent is approximately $35,000, escalating at 3% per annum. In July 2025, the Company and Nura Bio executed a sublease extension agreement effective May 2025, to extend the lease term for an additional 12 months until May 2026. Nura Bio is also responsible for its share of real estate taxes, utilities and other operating expenses applicable to the subleased space. During the three and nine months ended September 30, 2025 and 2024, the Company recognized sublease income of $0.2 million, $0.5 million, $0.2 million and $0.3 million, respectively, as reductions to operating expenses. Tim Kutzkey, Ph.D., a member of the Company’s board of directors, serves as the chairman of the board of directors of Nura Bio. Dr. Kutzkey also serves as Managing Partner of The Column Group, LLC, which is the general partner of certain limited partnerships which are significant stockholders of Nura Bio. The Column Group holds more than 5% of the Company’s common stock. Therefore, the agreement constitutes a related party transaction.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Note 9. Related Party Transactions

Surrozen, Inc./DE 10-Q