Stuart A Arbuckle
CIK 1557290 · EVP, COO · last filed 2026-06-25
Stuart A Arbuckle is an EVP, COO who has filed 159 SEC Form 4 insider transactions across 6 companies since 2012. The most recent filing, for RYTM, was dated Jun 25, 2026. Across all open-market trades the lifetime net is −$139.9M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $36.0M across reported positions.
"Disclosed insider exposure" sums this person's most-recently-reported share counts across each company they're an insider in, multiplied by the current underlying price. It is not net worth — it misses retail holdings, private investments, real estate, index funds, and any company where the person isn't an SEC-reporting insider. For informational purposes only.
$36.05M
6
159
-$139.91M
Holdings By Company
| Symbol | Role | Shares | Price | Disclosed Exposure | Lifetime OM Net | Filings | Latest Filed |
|---|---|---|---|---|---|---|---|
| RYTM | Director | 11,712 | $112.84 | $1.32M | $0 | 10 | 2026-06-25 |
| PRAX | Director | 2,537 | $370.68 | $940.4K | $0 | 2 | 2026-06-12 |
| ALNY | Director | 671 | $221.20 | $148.4K | $0 | 2 | 2026-05-22 |
| VRTX | EVP, COO | 63,508 | $529.65 | $33.64M | -$139.91M | 122 | 2025-07-02 |
| ImmunoGen, Inc. (IMGN) Delisted | Director | 0 | $31.23 | $0 | $0 | 11 | 2024-02-12 |
| Dare Bioscience, Inc. (CERU) Delisted | Director | 1,310 | — | — | $0 | 4 | 2017-01-05 |
Recent Filings
159 filings| Filed | Symbol | Action | Net Shares | Net $ | Link |
|---|---|---|---|---|---|
| 2026-06-25 | RYTM | Mixed | +4,712 | $0 | EDGAR |
| 2026-06-12 | PRAX | Grant (A) | +1,371 | $0 | EDGAR |
| 2026-05-22 | ALNY | Grant (A) | +671 | $0 | EDGAR |
| 2026-02-10 | PRAX | Grant (A) | +1,166 | $0 | EDGAR |
| 2026-01-07 | ALNY | Grant (A) | — | $0 | EDGAR |
| 2025-07-02 | VRTX | Tax (F) | −37,243 | -$16.77M | EDGAR |
| 2025-06-26 | RYTM | Grant (A) | — | $0 | EDGAR |
| 2025-06-23 | RYTM | Exer (M) | +4,000 | $0 | EDGAR |
| 2025-05-15 | VRTX | Grant (A) | +37,622 | $0 | EDGAR |
| 2025-02-28 | VRTX | Tax (F) | −7,071 | -$3.39M | EDGAR |
Notice (144 / 144/A): Form 144 is a notice of intent to sell restricted/control stock under Rule 144, filed before the sale; 144/A is an amendment. Many notices are pre-scheduled under Rule 10b5-1 plans. A Form 4 with code S typically follows within a few days when the planned sale executes; missing follow-up Form 4s suggest the notice was cancelled or modified.