Related Party Transaction	9 Months Ended
Sep. 30, 2025
Related Party Transactions [Abstract]
Related Party Transaction	12. Related Party Transaction In July 2022, the Company entered into an agreement with a non-profit foundation in which two members of the Company’s board of directors, including the Company’s Chief Executive Officer, at the time also served as board members of the foundation, whereby an aggregate $1.0 million contribution is being paid to the foundation over a four-year period, beginning in the third quarter of 2022, to support rare disease education and awareness. As a result, the Company recorded nil and $0.3 million, respectively, as research and development expense for the three and nine months ended September 30, 2025, and nil and $0.3 million, respectively, for the three and nine months ended September 30, 2024, respectively. A total of $1.0 million has been recorded as research and development expense for this agreement to date. There are no further obligations under this agreement.

Related Party Transaction

9 Months Ended

Sep. 30, 2025

12. Related Party Transaction

In July 2022, the Company entered into an agreement with a non-profit foundation in which two members of the Company’s board of directors, including the Company’s Chief Executive Officer, at the time also served as board members of the foundation, whereby an aggregate $1.0 million contribution is being paid to the foundation over a four-year period, beginning in the third quarter of 2022, to support rare disease education and awareness. As a result, the Company recorded nil and $0.3 million, respectively, as research and development expense for the three and nine months ended September 30, 2025, and nil and $0.3 million, respectively, for the three and nine months ended September 30, 2024, respectively. A total of $1.0 million has been recorded as research and development expense for this agreement to date. There are no further obligations under this agreement.

- 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
-Topic 850
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Ultragenyx Pharmaceutical Inc. 10-Q