Form 4: Ultragenyx Officer Sells Shares for Tax Withholding

Ultragenyx Pharmaceutical Inc.'s SVP, Chief Accounting Officer, Theodore Alan Huizenga, sold 85 shares of common stock to cover tax obligations related to RSU vesting.

Summary

• Theodore Alan Huizenga, SVP, Chief Accounting Officer of Ultragenyx Pharmaceutical Inc. (RARE), reported a transaction on December 29, 2025.
• Mr. Huizenga sold 85 shares of common stock at a price of $34.38 per share.
• The sale was conducted to pay required tax withholdings due to the vesting of Restricted Stock Units (RSUs).
• Following this transaction, Mr. Huizenga beneficially owns 50,450 shares of common stock.
• The reported beneficial ownership includes 293 shares acquired under the Company's A&R 2014 Employee Stock Purchase Plan on October 31, 2025.
• It also includes previously reported shares of common stock underlying RSUs that are subject to certain vesting conditions.

Sentiment

Score: 5

Explanation: The filing reports a routine insider transaction for tax withholding purposes, which is a neutral event and does not indicate positive or negative sentiment regarding the company's performance or outlook.

Future Outlook

This filing does not contain any forward-looking statements or guidance regarding the company's future performance or strategic direction.

Industry Context

This is a routine insider transaction for tax purposes, common across all industries when Restricted Stock Units (RSUs) vest, and does not reflect broader industry trends or competitive positioning.

Stakeholder Impact

• Shareholders: Minimal impact as this is a routine, tax-related sale by an officer and not indicative of a change in company fundamentals or management's confidence.

Key Dates

Recommendation

This Form 4 filing details a routine sale of shares by an officer to cover tax obligations upon RSU vesting. Such transactions are common and typically do not reflect a change in the officer's long-term view of the company or its fundamentals. Therefore, this specific filing does not provide sufficient new information to warrant a change from a 'hold' recommendation, assuming no other material information is available.

Keywords

Ultragenyx Pharmaceutical, RARE, Form 4, Insider Transaction, Stock Sale, Tax Withholding, RSU Vesting, Theodore Alan Huizenga, Employee Stock Purchase Plan