RARE · Insider Trading
Ultragenyx Pharmaceutical Inc.
Every open-market purchase and sale reported by RARE officers, directors and 10%+ beneficial owners on SEC Form 4, which must be filed within two business days of the transaction. Sales often reflect scheduled 10b5-1 plans or tax withholding rather than a directional view, so read counts alongside the size and the filer.
| Filed | Insider | Role | Type | Shares | Value |
|---|---|---|---|---|---|
| 2026-09-15 | Theodore Alan Huizenga | SVP, Chief Accounting Officer | Sell | −1,283 | −$17.41K |
| 2026-09-08 | Theodore Alan Huizenga | SVP, Chief Accounting Officer | Sell | −161 | −$2.25K |
| 2026-08-04 | Karah Herdman Parschauer | EVP and Chief Legal Officer | Sell | −1,900 | −$47.35K |
| 2026-08-04 | Howard Horn | Chief Financial Officer | Sell | −4,696 | −$117.02K |
| 2026-07-06 | Howard Horn | Chief Financial Officer | Sell | −4,698 | −$155.64K |
| 2026-06-15 | Corazon (Corsee) D. Sanders | Director | Sell | −2,000 | −$50.10K |
| 2026-06-15 | Karah Herdman Parschauer | EVP and Chief Legal Officer | Sell | −1,899 | −$46.75K |
| 2026-06-01 | Howard Horn | Chief Financial Officer | Sell | −4,653 | −$110.60K |
| 2026-05-18 | Deborah Dunsire | Director | A | +7,751 | — |
| 2026-05-18 | Daniel G Welch | Director | A | +7,751 | — |
| 2026-05-18 | Michael Narachi | Director | A | +7,751 | — |
| 2026-05-18 | Matthew K Fust | Director | A | +7,751 | — |
| 2026-05-18 | Corazon (Corsee) D. Sanders | Director | A | +7,751 | — |
| 2026-05-18 | Amrit Ray | Director | A | +7,751 | — |
| 2026-05-18 | Shehnaaz Suliman | Director | MIXED | +2,011 | −$144.19K |
| 2026-05-06 | Eric Crombez | EVP and Chief Medical Officer | Sell | −344 | −$8.59K |
| 2026-05-04 | Howard Horn | Chief Financial Officer | Sell | −4,683 | −$116.61K |
| 2026-04-24 | Theodore Alan Huizenga | SVP, Chief Accounting Officer | A | +20,241 | — |
| 2026-04-20 | Howard Horn | Chief Financial Officer | A | +34,674 | — |
| 2026-04-20 | Eric Crombez | EVP and Chief Medical Officer | A | +34,674 | — |
| 2026-04-20 | Erik Harris | EVP & Chief Commercial Officer | A | +28,895 | — |
| 2026-04-20 | Karah Herdman Parschauer | EVP and Chief Legal Officer | A | +28,895 | — |
| 2026-04-20 | John Richard Pinion | See Remarks | A | +23,116 | — |
| 2026-04-20 | Dennis Karl Huang | See Remarks | A | +23,116 | — |
| 2026-04-20 | Emil D Kakkis | President & CEO | A | +76,745 | — |
| 2026-04-02 | Howard Horn | Chief Financial Officer | Sell | −4,683 | −$98.20K |
| 2026-03-10 | Karah Herdman Parschauer | EVP and Chief Legal Officer | Sell | −9,526 | −$208.31K |
| 2026-03-03 | Dennis Karl Huang | See Remarks | MIXED | +10,138 | −$23.37K |
| 2026-03-03 | Eric Crombez | EVP and Chief Medical Officer | MIXED | +4,614 | −$160.26K |
| 2026-03-03 | Howard Horn | Chief Financial Officer | MIXED | −3,901 | −$227.54K |
| 2026-03-03 | Theodore Alan Huizenga | SVP, Chief Accounting Officer | MIXED | −1,780 | −$40.67K |
| 2026-03-03 | Karah Herdman Parschauer | EVP and Chief Legal Officer | MIXED | +3,002 | −$185.48K |
| 2026-03-03 | Emil D Kakkis | President & CEO | MIXED | +16,773 | −$1.24M |
| 2026-03-03 | Erik Harris | EVP & Chief Commercial Officer | MIXED | +1,104 | −$240.29K |
| 2026-03-03 | John Richard Pinion | See Remarks | MIXED | +1,108 | −$228.66K |
| 2026-02-03 | Howard Horn | Chief Financial Officer | Sell | −3,061 | −$72.12K |
| 2026-01-05 | Howard Horn | Chief Financial Officer | Sell | −3,150 | −$71.95K |
| 2025-12-30 | Theodore Alan Huizenga | SVP, Chief Accounting Officer | Sell | −85 | −$2.92K |
| 2025-12-11 | Howard Horn | Chief Financial Officer | Sell | −3,081 | −$112.09K |
| 2025-10-14 | Howard Horn | Chief Financial Officer | Sell | −7,942 | −$250.25K |
| 2025-09-19 | Theodore Alan Huizenga | SVP, Chief Accounting Officer | Sell | −64 | −$1.87K |
| 2025-09-12 | Karah Herdman Parschauer | EVP and Chief Legal Officer | Sell | −2,450 | −$76.37K |
| 2025-09-08 | Theodore Alan Huizenga | SVP, Chief Accounting Officer | Sell | −84 | −$2.64K |
| 2025-06-23 | Corazon (Corsee) D. Sanders | Director | Sell | −2,405 | −$89.92K |
| 2025-05-19 | Amrit Ray | Director | A | +5,740 | — |
| 2025-05-19 | Deborah Dunsire | Director | A | +5,740 | — |
| 2025-05-19 | Matthew K Fust | Director | A | +5,740 | — |
| 2025-05-19 | Michael Narachi | Director | A | +5,740 | — |
| 2025-05-19 | Corazon (Corsee) D. Sanders | Director | A | +5,740 | — |
| 2025-05-19 | Daniel G Welch | Director | A | +5,740 | — |
| Insider | Role | Shares Held | Value |
|---|---|---|---|
| Emil D Kakkis | President & CEO | 935,739 | $13.92M |
| Thomas Richard Kassberg | CBO & EVP | 271,266 | $4.04M |
| Dennis Karl Huang | See Remarks | 147,845 | $2.20M |
| John Richard Pinion | See Remarks | 133,142 | $1.98M |
| Erik Harris | EVP & Chief Commercial Officer | 118,410 | $1.76M |
| Eric Crombez | EVP and Chief Medical Officer | 111,189 | $1.65M |
| Howard Horn | Chief Financial Officer | 96,295 | $1.43M |
| Karah Herdman Parschauer | EVP and Chief Legal Officer | 92,562 | $1.38M |
| Theodore Alan Huizenga | SVP, Chief Accounting Officer | 67,863 | $1.01M |
| Daniel G Welch | Director | 40,441 | $601.76K |
| Michael Narachi | Director | 40,441 | $601.76K |
| Deborah Dunsire | Director | 38,566 | $573.86K |
| Matthew K Fust | Director | 33,696 | $501.40K |
| Shehnaaz Suliman | Director | 33,691 | $501.32K |
| Amrit Ray | Director | 31,116 | $463.01K |
| Corazon (Corsee) D. Sanders | Director | 21,095 | $313.89K |
Form 4 reports a change in beneficial ownership by an officer, director or 10%+ holder, and must be filed within two business days of the transaction — so this is close to real time, unlike the 45-day-lagged 13F institutional data.
Transaction codes matter more than the raw buy/sell count. Code P is an open-market purchase — an insider choosing to buy with their own money, which is the signal most research treats as informative. Code S is a sale, but sales are frequently pre-scheduled under a 10b5-1 plan or cover tax withholding on vesting equity, so a run of sales often says nothing directional. Codes A and M are grants and option exercises rather than open-market decisions.
Full filing history and per-insider positions are on the RARE quote page; the site-wide leaderboard is on the insider transactions hub.
Market data may be delayed, incomplete, or inaccurate. Not a recommendation to buy, sell, or hold any security. Verify quotes with your broker before trading. See Terms §17.