Theodore Alan Huizenga - 05 Sep 2025 Form 4 Insider Report for Ultragenyx Pharmaceutical Inc. (RARE)

Role: SVP, Chief Accounting Officer
Signature: /s/ Karah Parschauer, attorney-in-fact
Issuer symbol: RARE
Transactions as of: 05 Sep 2025
Net transactions value: -$2,637
Form type: 4
Filing time: 08 Sep 2025, 14:01:44 UTC
Previous filing: 04 Mar 2025
Next filing: 19 Sep 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Huizenga Theodore Alan	SVP, Chief Accounting Officer	C/O ULTRAGENYX PHARMACEUTICAL INC., 60 LEVERONI COURT, NOVATO	/s/ Karah Parschauer, attorney-in-fact	08 Sep 2025	0001603347

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	RARE	Common Stock	Sale	$2,637	-84	-0.17%	$31.39	50,306	05 Sep 2025	Direct	F1, F2, F3

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	Represents shares sold to pay required tax withholdings due to the vesting of RSUs.
F2	Includes 266 shares acquired under the Company's A&R 2014 Employee Stock Purchase Plan on April 30, 2025.
F3	Includes previously reported shares of common stock underlying RSUs granted to the Reporting Person, which are subject to certain vesting conditions.