John Maraganore
CIK 1180432 · Chief Executive Officer · last filed 2026-10-22
John Maraganore is a Chief Executive Officer who has filed 124 SEC Form 4 insider transactions across 11 companies since 2007. The most recent filing shows the insider bought $248.9K of RAPP on Oct 22, 2026. Across all open-market trades the lifetime net is −$120.8M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $55.5M across reported positions. 90 SEC filings were submitted jointly with ALNYLAM PHARMACEUTICALS, INC.
"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.
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 monthDollar 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
latestMost 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
CAMBRIDGE, MA 02139
Holdings By Company
| Symbol | Role | Shares | Price | Disclosed Exposure | Lifetime OM Net | Filings | Latest Filed |
|---|---|---|---|---|---|---|---|
| RAPP | Director | 8,239 | $25.33 | $208.7K | $248.9K | 3 | 2026-10-22 |
| CTY | Director | 1,789,199 | — | — | $0 | 1 | 2026-10-19 |
| TAK | Director | 13,800 | $20.43 | $281.9K | $0 | 1 | 2026-07-06 |
| KYMR | Director | — | $114.84 | — | $0 | 5 | 2026-06-25 |
| BEAM | Director | — | $23.79 | — | $0 | 6 | 2026-06-05 |
| COAG | Director | 35,948 | $36.02 | $1.29M | $0 | 1 | 2026-05-04 |
| PROK | Director | — | $1.36 | — | $0 | 1 | 2023-07-03 |
| AGIO | Director | 30,028 | $36.85 | $1.11M | -$1.80M | 18 | 2022-06-23 |
| ALNY | Chief Executive Officer | 231,115 | $227.66 | $52.62M | -$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
124 filings| Filed | Symbol | Action | Net Shares | Net $ | Link |
|---|---|---|---|---|---|
| 2026-10-22 | RAPP | Buy (P) | +9,411 | $248.9K | EDGAR |
| 2026-10-19 | CTY | Mixed | +610,759 | $0 | EDGAR |
| 2026-07-06 | TAK | Mixed | +3,800 | $0 | EDGAR |
| 2026-06-25 | KYMR | Grant (A) | — | $0 | EDGAR |
| 2026-06-10 | RAPP | Grant (A) | — | $0 | EDGAR |
| 2026-06-05 | BEAM | Grant (A) | — | $0 | EDGAR |
| 2026-05-04 | COAG | Mixed | +35,948 | $0 | EDGAR |
| 2025-06-26 | KYMR | Grant (A) | — | $0 | EDGAR |
| 2025-06-18 | RAPP | Grant (A) | — | $0 | EDGAR |
| 2025-06-06 | BEAM | Grant (A) | — | $0 | 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.