🕵️ Amylyx Pharmaceuticals, Inc. ($AMLX)

SEC insider & ownership activity, last 12 months · CIK 1658551 · every row links its SEC filing

Over the last 12 months insiders sold $7.9M against $152K of open-market buying. Justin B. Klee sold $3.0M (Sep–Mar). Blackrock, Inc. added 5.5% → 7.1%. No red-flag 8-Ks in the window.

🚨 2 signals active — planned-vs-executed verdicts, pre-event flags, and cluster context live in the API and the alerts bot.
Aug 2025: net -$246K Sep 2025: net -$1.3M Oct 2025: net +$0 Nov 2025: net +$0 Dec 2025: net +$6K Jan 2026: net -$4.0M Mar 2026: net -$1.2M Mar 2026: net -$1.2M Apr 2026: net +$0 May 2026: net +$51K Jun 2026: net +$0 Jul 2026: net -$539K
Monthly net open-market insider flow, last 12 months (up = net buying)

Insider flow

1 buyer, $152K (2 lots) · 5 sellers, $7.9M (29 lots)

InsiderBuysBoughtSellsSoldLast
Justin B. Klee0 7$3.0MMar 2, 2026
Joshua B. Cohen0 7$3.0MMar 2, 2026
Mazzariello Gina0 8$1.1MJul 10, 2026
Camille L. Bedrosian0 3$364KMar 2, 2026
James M. Frates0 4$359KMar 2, 2026
Firestone Karen2$152K 0May 21, 2026

5%+ holders

HolderStakeClassScheduleEvent
FMR LLC 15.0% 13GFeb 5, 2026 filing ↗
Abigail P. Johnson 15.0% 13GFeb 5, 2026 filing ↗
Perceptive Advisors LLC 7.5% 13GMay 15, 2026 filing ↗
Joseph Edelman 7.5% 13GMay 15, 2026 filing ↗
Perceptive Life Sciences Master Fund, Ltd. 7.5% 13GMay 15, 2026 filing ↗
Blackrock, Inc. 7.1% 13GJan 21, 2026 filing ↗
TCG Crossover GP II, LLC 5.7% 13GFeb 17, 2026 filing ↗
TCG Crossover Fund II, L.P. 5.7% 13GFeb 17, 2026 filing ↗
Chen Yu 5.7% 13GFeb 17, 2026 filing ↗
Commodore Capital LP 5.1% 13GNov 17, 2025 filing ↗
Commodore Capital Master LP 5.1% 13GNov 17, 2025 filing ↗
Robert Egen Atkinson 5.1% 13GNov 17, 2025 filing ↗
Michael Kramarz 5.1% 13GNov 17, 2025 filing ↗

Planned insider sales (Form 144)

SellerPlannedApprox. sale date
Gina Mazzariello$536KJul 9, 2026 filing ↗
Mazzariello Gina$99KMar 2, 2026 filing ↗
Joshua B. Cohen$424KMar 2, 2026 filing ↗
Justin B. Klee$424KMar 2, 2026 filing ↗
Camille L. Bedrosian$94KMar 2, 2026 filing ↗
James M. Frates$115KMar 2, 2026 filing ↗
Mazzariello Gina$48KFeb 23, 2026 filing ↗
Joshua B. Cohen$228KFeb 2, 2026 filing ↗
Justin B. Klee$228KFeb 2, 2026 filing ↗
Mazzariello Gina$51KFeb 2, 2026 filing ↗
James M. Frates$52KFeb 2, 2026 filing ↗
Justin Klee$27KJan 16, 2026 filing ↗
Joshua Cohen$27KJan 16, 2026 filing ↗
Joshua Cohen$1.9MJan 15, 2026 filing ↗
Justin Klee$1.9MJan 15, 2026 filing ↗
James M. Frates$37KJan 6, 2026 filing ↗
Justin B. Klee$86KJan 6, 2026 filing ↗
Joshua B. Cohen$86KJan 6, 2026 filing ↗
Camille L. Bedrosian$94KDec 1, 2025 filing ↗
Gina Mazzariello$235KAug 12, 2025 filing ↗

Material events (8-K)

ItemEvent date
Shareholder vote (5.07)Jun 4, 2026 filing ↗
Earnings (2.02)May 7, 2026 filing ↗
Financial Statements and Exhibits (9.01)May 7, 2026 filing ↗
Reg FD disclosure (7.01)Mar 24, 2026 filing ↗
Financial Statements and Exhibits (9.01)Mar 24, 2026 filing ↗
Earnings (2.02)Mar 3, 2026 filing ↗
Financial Statements and Exhibits (9.01)Mar 3, 2026 filing ↗
Reg FD disclosure (7.01)Jan 8, 2026 filing ↗
Other events (8.01)Jan 8, 2026 filing ↗
Financial Statements and Exhibits (9.01)Jan 8, 2026 filing ↗
Earnings (2.02)Nov 6, 2025 filing ↗
Financial Statements and Exhibits (9.01)Nov 6, 2025 filing ↗
Material agreement (1.01)Sep 9, 2025 filing ↗
Financial Statements and Exhibits (9.01)Sep 9, 2025 filing ↗
Other events (8.01)Aug 27, 2025 filing ↗
Earnings (2.02)Aug 7, 2025 filing ↗
Financial Statements and Exhibits (9.01)Aug 7, 2025 filing ↗