Company · Ownership research

Ultragenyx Pharmaceutical Inc. RARE

CIK 0001515673

Form 4 transactions dated Nov 1, 2023 to Nov 12, 2026, as reported to the SEC.

Insider trading Initial holdings Institutional holders

This page lists 30 of 36 rows; the complete set is available through the API.

Insider filings on file run through Oct 19, 2026.

Insider purchases & sales

Purchased: $0.00
Sold: $19.86M

Nov 1, 2023 – Oct 19, 2026
Available records · partial months are marked ·

202510 of 19 preview events

Date	Insider	Activity	Trade value (USD)	% of prior holding
Dec 29, 2025	Huizenga Theodore Alan SVP, Chief Accounting Officer	Sale	$2.92K 85 shares sold	0.17% sold Direct holding	▾
Dec 10, 2025	Horn Howard Chief Financial Officer	Sale	$112.09K 3,081 shares sold	3.14% sold Direct holding	▾
Oct 13, 2025	Horn Howard Chief Financial Officer	Sale	$250.25K 7,942 shares sold	7.48% sold Direct holding	▾
Sep 18, 2025	Huizenga Theodore Alan SVP, Chief Accounting Officer	Sale	$1.87K 64 shares sold	0.13% sold Direct holding	▾
Sep 12, 2025	Parschauer Karah Herdman EVP and Chief Legal Officer	Sale	$76.37K 2,450 shares sold	3.24% sold Direct holding	▾
Sep 5, 2025	Huizenga Theodore Alan SVP, Chief Accounting Officer	Sale	$2.64K 84 shares sold	0.17% sold Direct holding	▾
Jun 20, 2025	Sanders Corazon (Corsee) D. Director	Sale	$89.92K 2,405 shares sold	13.55% sold Direct holding	▾
May 5, 2025	Crombez Eric EVP and Chief Medical Officer	Sale	$20.40K 520 shares sold	0.72% sold Direct holding	▾
Apr 21, 2025	Crombez Eric EVP and Chief Medical Officer	Sale	$8.50K 242 shares sold	0.34% sold Direct holding	▾
Mar 6, 2025	Horn Howard Chief Financial Officer	Sale	$72.11K 1,785 shares sold	1.65% sold Direct holding	▾

Showing 19 / 19 record groups in 2025. The complete set is available through the API.

Ultragenyx Pharmaceutical Inc. · RARE

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The initial HTML of this page carries its exact data as script#research-data (JSON): values, units, scope, preview limits and SEC sources. Read it directly, no script or API key needed; script#research-access says what needs an account. For the year shown, this page lists 19 of 19 purchase / sale groups and 30 of 36 other groups; the totals and the monthly series cover the whole window.

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Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.

Non-cancelled, non-derivative purchase (P) and sale (S) rows dated inside the public window, as reported. Share totals are on today's split-adjusted basis. Includes open-market and private transactions. Data after the latest filing is not asserted complete and is not zero-filled. A grouped event shares filing, transaction date, security, code, direction, ownership bucket and source. Derivative groups also match underlying security, exercise price, exercise/expiration dates and footnote references. Reported rows are retained; P/S price lots can be grouped. Post-transaction balances are never summed.