44% buyers of institutions opening or closing positions this quarter
8 more exits than new buyers, ownership rose 20.18 percentage points vs the prior quarter, and no widely-followed fund managers in the top 25.
44% buyers of institutions opening or closing positions this quarter
139.4% institutional ownership
Saturn V Capital portfolio allocation
Institutional ownership vs Biotechnology peers
No Form 4 insider transactions on file
Latest positioning in AMLX across 13F flow, ownership shift, marquee holders, and holder-count growth.
Ranked by reported Q1 2026 13F market value
Share of total reported institutional value in AMLX held by the largest 10 / 25 filers.
| # | Institution | Shares Held | Market Value | QoQ Change | Ownership % | % of Fund |
|---|---|---|---|---|---|---|
| 1 | FMR LLC | 16.6M | $231.2M | +0.7% | 20.007% | 0.01% |
| 2 | BlackRock, Inc. | 8.8M | $122.7M | -2.5% | 10.621% | 0.00% |
| 3 | PERCEPTIVE ADVISORS LLC | 8.3M | $115.2M | 0.0% | 9.967% | 2.25% |
| 4 | TCG Crossover Management, LLC | 6.2M | $86.8M | 0.0% | 7.511% | 2.48% |
| 5 | COMMODORE CAPITAL LP | 5.7M | $78.5M | 0.0% | 6.797% | 4.54% |
| 6 | JANUS HENDERSON GROUP PLC | 5.0M | $69.3M | +11.7% | 5.998% | 0.03% |
| 7 | Saturn V Capital Management LP | 4.3M | $60.5M | -3.3% | 5.233% | 10.95% |
| 8 | VANGUARD CAPITAL MANAGEMENT LLC | 4.1M | $57.6M | — | 4.982% | 0.00% |
| 9 | ADAGE CAPITAL PARTNERS GP, L.L.C. | 3.6M | $49.5M | +28.2% | 4.284% | 0.08% |
| 10 | First Light Asset Management, LLC | 3.2M | $44.3M | -4.9% | 3.838% | 3.97% |
| 11 | DRIEHAUS CAPITAL MANAGEMENT LLC | 3.0M | $41.5M | -3.9% | 3.594% | 0.31% |
| 12 | GOLDMAN SACHS GROUP INC | 2.6M | $36.5M | +0.5% | 3.159% | 0.00% |
| 13 | STATE STREET CORP | 2.4M | $32.8M | +14.2% | 2.843% | 0.00% |
| 14 | FRANKLIN RESOURCES INC | 2.3M | $31.4M | +88.4% | 2.721% | 0.01% |
| 15 | GEODE CAPITAL MANAGEMENT, LLC | 2.2M | $30.7M | +2.1% | 2.660% | 0.00% |
| 16 | MORGAN STANLEY | 2.2M | $30.2M | -7.8% | 2.617% | 0.00% |
| 17 | Almitas Capital LLC | 2.1M | $29.5M | 0.0% | 2.553% | 6.67% |
| 18 | GREAT POINT PARTNERS LLC | 1.8M | $24.3M | 0.0% | 2.105% | 5.59% |
| 19 | 683 Capital Management, LLC | 1.6M | $22.6M | -1.4% | 1.957% | 1.18% |
| 20 | Jones Hill Capital LP | 1.6M | $22.2M | — | 1.923% | 4.76% |
| 21 | EVENTIDE ASSET MANAGEMENT, LLC | 1.5M | $21.0M | +0.1% | 1.821% | 0.35% |
| 22 | BANK OF AMERICA CORP /DE/ | 1.3M | $18.5M | -0.4% | 1.601% | 0.00% |
| 23 | DEUTSCHE BANK AG\ | 1.3M | $17.6M | -4.9% | 1.525% | 0.01% |
| 24 | Siren, L.L.C. | 1.2M | $17.1M | — | 1.480% | 0.47% |
| 25 | BALYASNY ASSET MANAGEMENT LLC | 1.1M | $15.4M | +28.9% | 1.332% | 0.02% |
denotes a marquee investor (Buffett, Burry, ARK, Tiger Global, Pershing Square, Baupost and other widely-followed managers). “% of Fund” shows how much of that investor’s total 13F portfolio is invested in AMLX — a direct measure of their conviction.
Filings activity in AMLX during Q1 2026, grouped by how each filer changed its position.
Institutions that opened a new AMLX position in Q1 2026
Institutions that fully closed their AMLX position in Q1 2026
8 quarters of 13F filings · Δ columns show change vs prior quarter
| Quarter | Inst. Holders | Δ Holders | Ownership % | Δ Ownership | Total 13F Value | Δ Value |
|---|---|---|---|---|---|---|
| Q1 2026 | 169 | 4.5% | 139.41% | +20.18 pp | $1.59B | +17% |
| Q4 2025 | 177 | +8.6% | 119.23% | 9.83 pp | $1.36B | 7.6% |
| Q3 2025 | 163 | +26% | 129.06% | +83.49 pp | $1.47B | +183% |
| Q2 2025 | 129 | 3.0% | 45.57% | +23.64 pp | $518M | +108% |
| Q1 2025 | 133 | +14% | 21.93% | +6.44 pp | $249M | +42% |
| Q4 2024 | 117 | +9.3% | 15.49% | +4.23 pp | $176M | +37% |
| Q3 2024 | 107 | 5.3% | 11.26% | +4.41 pp | $128M | +64% |
| Q2 2024 | 113 | — | 6.85% | — | $78M | — |
Source: SEC 13F institutional filings. Ownership % requires market cap data and will show once linked. Δ columns compare to the immediately prior filed quarter.
No recent Form 4 insider transactions on file for AMLX.
Quick answers to the most common questions about buying AMLX stock.
Based on Q1 2026 13F filings, institutional ownership of Amylyx Pharmaceuticals, Inc. stands at 139.4%, held across 169 reporting institutions.
FMR LLC is the largest reported institutional holder of AMLX, with approximately 16,630,541 shares worth $0.23B as of Q1 2026.
No marquee "smart money" managers (Berkshire, Burry, ARK, Tiger Global, Pershing Square, Baupost, etc.) currently appear among the top 25 institutional holders of AMLX.
Our composite Smart Money Score for AMLX is 43 out of 100 (Neutral). It combines net institutional buying activity, ownership shift, marquee investor presence, and holder-count growth.
29 institutions opened new positions in AMLX during Q1 2026, while 37 fully exited. 105 added to existing positions and 35 trimmed.
AMLX institutional ownership rose by 20.18 percentage points quarter-over-quarter, with a net change of — holders.
The top 10 institutions account for 57.8% of all reported 13F value in AMLX, and the top 25 account for 82.5%.
All data is sourced from SEC Form 13F filings, which institutional investment managers with at least $100M in assets are required to file each quarter. We process every 13F filing from EDGAR and recompute the aggregates after each cycle. Insider transactions are sourced from Form 4 filings.