John Maraganore

CIK 1180432 · Chief Executive Officer · last filed 2026-10-22

"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
$54.97M
Companies
11
Total Filings
124
Lifetime Open-Market Net
-$120.82M

Charts

Trading activity, where the exposure sits, and each trade against the stock price.

ALNY price and trades

Daily close with each Form 4 filing on this company marked: green = open-market buy, red = open-market sale, purple = grants, exercises, gifts and other non-market transactions. Marker size scales with the dollar value.

Shares held

Shares owned after each reported transaction on this company (direct holdings as reported).

Open-market buying and selling

by month

Dollar value of open-market purchases (code P, up) and sales (code S, down) across all companies, by filing month. Grants, exercises and gifts are excluded.

Exposure by company

latest
OfficerDirector10% owner* stale (no filing in 3 yrs)

Most recently reported shares × current price. Faded bars (*) have had no filing in 3 years, so the person may no longer hold them. Click a bar to chart that company.

Filer Profile

Reported Address
75 SIDNEY ST
CAMBRIDGE, MA 02139
Related Filers
ALNYLAM PHARMACEUTICALS, INC. — 90 joint filings, latest 2021-12-23
bluebird bio, Inc. — 11 joint filings, latest 2017-09-18
Beam Therapeutics Inc. — 7 joint filings, latest 2026-06-05
MILLENNIUM PHARMACEUTICALS INC — 2 joint filings, latest 2002-11-18
TAKEDA PHARMACEUTICAL CO LTD — 2 joint filings, latest 2026-07-06
Profile details as reported on the filer's SEC submissions — for individual insiders the address is often in care of the issuer. Related filers are identified from jointly filed SEC submissions and shared reported addresses. View filings on SEC EDGAR.

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
RAPP Director 8,239 $27.91 $230.0K $248.9K 3 2026-10-22
CTY Director 1,789,199 — — $0 1 2026-10-19
TAK Director 13,800 $20.29 $279.9K $0 1 2026-07-06
KYMR Director — $118.66 — $0 5 2026-06-25
BEAM Director — $24.37 — $0 6 2026-06-05
COAG Director 35,948 $37.81 $1.36M $0 1 2026-05-04
PROK Director — $1.48 — $0 1 2023-07-03
AGIO Director 30,028 $37.49 $1.13M -$1.80M 18 2022-06-23
ALNY Chief Executive Officer 231,115 $224.89 $51.98M -$114.58M 77 2021-12-23
bluebird bio, Inc. (BLUE) Delisted Director 1,236 $4.97 $6.1K -$4.68M 9 2017-09-18
Regulus Therapeutics Inc. (RGLS) Delisted Director 51,254 $8.16 $418.2K $0 1 2012-10-11

Recent Filings · Page 10 of 13

124 filings
Insider 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
2014-12-16 ALNY Mixed +8,205 $75.0K EDGAR
2014-09-19 ALNY Mixed −1,700 -$7.98M EDGAR
2014-07-14 bluebird bio, Inc. (BLUE) Delisted Buy (P) +2,941 $100.0K EDGAR
2014-02-04 ALNY Exer (M) +46,331 $314.1K EDGAR
2013-12-18 ALNY Grant (A) — $0 EDGAR
2013-12-06 AGIO Grant (A) — $0 EDGAR
2013-10-15 ALNY Exer (M) +12,665 $85.9K EDGAR
2013-09-24 ALNY Grant (A) — $0 EDGAR
2013-09-12 ALNY Mixed — -$3.22M EDGAR
2013-08-16 ALNY Mixed — -$2.88M EDGAR
Showing 91–100 of 124
Page 10 of 13
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.