John Cox
CIK 1498428 · CEO & President · last filed 2026-08-17
"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.
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Disclosed Exposure
$18.36M
Companies
5
Total Filings
82
Lifetime Open-Market Net
-$13.24M
Holdings By Company
Latest on-record share count from this person's most recent non-derivative Form 4 transaction in each company. Disclosed exposure = shares × current underlying price.
| Symbol | Role | Shares | Price | Disclosed Exposure | Lifetime OM Net | Filings | Latest Filed |
|---|---|---|---|---|---|---|---|
| DYN | CEO & President | 381,165 | $26.00 | $9.91M | $1.49M | 14 | 2026-08-17 |
| Sigilon Therapeutics, Inc. (SGTX) Delisted | Director | 342 | $22.47 | $7.7K | $0 | 5 | 2023-08-11 |
| RGEN | Director | 923 | $166.15 | $153.4K | -$4.07M | 10 | 2020-03-26 |
| Bioverativ Inc. (BIVV) Delisted | Chief Executive Officer | 0 | — | — | $0 | 9 | 2018-03-08 |
| BIIB | EVP Pharmaceutical Oper & Tech | 39,045 | $212.55 | $8.30M | -$10.66M | 36 | 2016-04-05 |
Recent Filings · Page 3 of 9
82 filingsInsider activity across all companies, newest first. Form 4 rows are post-trade confirmations (buys, sells, grants, exercises). Notice (144) rows are pre-trade notices of intent to sell restricted or control stock under Rule 144 — they may not all execute. Compare adjacent dates to see which notices became actual sales.
| Filed | Symbol | Action | Net Shares | Net $ | Link |
|---|---|---|---|---|---|
| 2024-09-04 | DYN | Buy (P) | +32,000 | $1.06M | EDGAR |
| 2024-03-27 | DYN | Grant (A) | — | $0 | EDGAR |
| 2023-08-11 | Sigilon Therapeutics, Inc. (SGTX) Delisted | Disp (D) | −341 | $0 | EDGAR |
| 2023-05-22 | Sigilon Therapeutics, Inc. (SGTX) Delisted | Grant (A) | — | $0 | EDGAR |
| 2022-05-27 | Sigilon Therapeutics, Inc. (SGTX) Delisted | Grant (A) | — | $0 | EDGAR |
| 2021-06-28 | Sigilon Therapeutics, Inc. (SGTX) Delisted | Grant (A) | — | $0 | EDGAR |
| 2020-12-10 | Sigilon Therapeutics, Inc. (SGTX) Delisted | Conv (C) | +4,444 | $0 | EDGAR |
| 2020-03-26 | RGEN | Sell (S) | −1,858 | -$179.7K | EDGAR |
| 2020-03-20 | RGEN | Mixed | — | -$1.90M | EDGAR |
| 2020-03-05 | RGEN | Mixed | — | -$804.8K | EDGAR |
Form 4 codes: P = open-market purchase · S = open-market sale · A = grant/award · M = option exercise · F = tax withholding at vest · G = bona-fide gift · D = disposition to issuer · J = other (see filing footnote). Only P / S codes carry directional signal.
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.
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.