John Cox

CIK 1498428 · CEO & President · last filed 2026-05-14

"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

$15.00M

Companies

5

Total Filings

72

Lifetime Open-Market Net

-$13.06M

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 388,834 $18.19 $7.07M $1.67M 12 2026-05-14
Sigilon Therapeutics, Inc. (SGTX) Delisted Director 4,444 $22.47 $99.9K $0 5 2023-08-11
RGEN Director 923 $130.59 $120.5K -$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 $200.05 $7.81M -$10.66M 36 2016-04-05

Recent Filings · Page 5 of 8

72 filings
Form 4 transactions across all companies, newest first.
Filed Symbol Action Net Shares Net $ Link
2015-03-26 BIIB Mixed −6,944 -$5.06M EDGAR
2015-02-25 BIIB Grant (A) $0 EDGAR
2015-02-17 BIIB Mixed +1,977 -$690.5K EDGAR
2015-02-10 BIIB Mixed +4,967 -$1.49M EDGAR
2014-02-25 BIIB Mixed +1,370 -$426.3K EDGAR
2014-02-14 BIIB Mixed +1,187 -$342.1K EDGAR
2014-02-11 BIIB Mixed +5,061 -$1.15M EDGAR
2013-12-04 BIIB Gift (G) −200 $0 EDGAR
2013-11-19 RGEN Grant (A) $0 EDGAR
2013-05-07 BIIB Tax (F) −866 -$189.5K EDGAR
Showing 4150 of 72
Page 5 of 8
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.