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 7 of 8

72 filings
Form 4 transactions across all companies, newest first.
Filed Symbol Action Net Shares Net $ Link
2011-04-15 BIIB Mixed -$843.1K EDGAR
2011-04-13 BIIB Mixed -$207.6K EDGAR
2011-04-01 BIIB Mixed -$83.8K EDGAR
2011-03-03 BIIB Sell (S) −4,041 -$283.3K EDGAR
2011-02-28 BIIB Tax (F) −1,202 -$80.8K EDGAR
2011-02-25 BIIB Mixed +1,458 -$45.4K EDGAR
2011-02-18 BIIB Sell (S) −1,843 -$123.6K EDGAR
2011-02-15 BIIB Tax (F) −910 -$59.9K EDGAR
2011-02-11 BIIB Grant (A) $0 EDGAR
2010-11-10 BIIB Sell (S) −773 -$48.6K EDGAR
Showing 6170 of 72
Page 7 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.