Who owns NAMS (NAMS)
Which tracked institutional funds hold NAMS, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See NAMS company fundamentals →
Ownership as of the 2026-Q1 13F filings. 13F is disclosed up to 45 days after quarter-end, so the most recent quarter fills in over the following weeks.
How the tape is positioned
36 tracked funds added or opened NAMS while 78 trimmed or exited it between 2025-Q4 and 2026-Q1 — the tape is split. When large holders disagree on a name, the funds moving first are sometimes ahead of the story.
A prompt to read the filings, not a verdict. 13F is a quarter-end snapshot disclosed up to 45 days late; a fund adds or exits for mandate, benchmark, and timing reasons that have nothing to do with a view on the stock. This is a starting question, not a signal to trade.
Conviction spread
NAMS’s largest tracked holder by dollar value, Frazier Life Sciences Management, L.P., sizes it at 14.0% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 13.9pp conviction gap — its largest holder concentrates the name more heavily than the typical one.
Book-share is each fund’s reported value in NAMS divided by its whole reported 13F book, so it is comparable across funds of different sizes and is unaffected by stock splits. A higher share means a fund has committed more of its book to the name — a starting question about conviction, not a verdict or a signal to trade.
Institutional & insider positioning
Between 2025-Q4 and 2026-Q1, across 169 tracked filers holding NAMS, 91 increased or opened the position and 92 reduced or closed it; over the same quarter, open-market insider Form 4 buying and selling roughly offset.
This fuses two public signals for the same quarter — how tracked institutions changed their positions and whether insiders bought or sold in the open market. It describes what was filed; it is a starting question, not a verdict or a signal to trade.
New buyers & exits
Funds opening or closing a position in NAMS between the 2025-Q4 and 2026-Q1 13F filings, and the largest changes among funds holding it in both. New buyers and exits are counted on fund presence (split-invariant); adds and trims are measured on reported value.
New buyers 15
- WESTFIELD CAPITAL MANAGEMENT CO LP$71M
- SEB Asset Management AB$9M
- MARSHALL WACE, LLP$8M
- PEREGRINE CAPITAL MANAGEMENT LLC$6M
- VICTORY CAPITAL MANAGEMENT INC$6M
- VANGUARD PORTFOLIO MANAGEMENT LLC$4M
Full exits 12
- Lisanti Capital Growth, LLC$6M
- VANGUARD GROUP INC$6M
- PRICE T ROWE ASSOCIATES INC /MD/$4M
- JTC Employer Solutions Trustee Ltd$3M
- Centiva Capital, LP$3M
- Jain Global LLC$2M
Largest adds
- FMR LLC$56M
- BNP PARIBAS ASSET MANAGEMENT Holding S.A.$24M
- AMERIPRISE FINANCIAL INC$19M
- BANK OF AMERICA CORP /DE/$11M
- KENNEDY CAPITAL MANAGEMENT LLC$7M
- Capital World Investors$5M
Largest trims
- Frazier Life Sciences Management, L.P.$52M
- JENNISON ASSOCIATES LLC$34M
- RA CAPITAL MANAGEMENT, L.P.$29M
- FCPM III SERVICES B.V.$28M
- Capital International Investors$26M
- Pictet Asset Management Holding SA$26M
Institutional holders
One row per tracked fund, largest reported value first. “% of value” is the fund’s share of this security’s tracked institutional value — not of shares outstanding. Rows marked stale are from an earlier filing than the security’s latest quarter — that fund is absent from the newest snapshot (position exited, or reported under a different name).
| Fund | Shares | Reported value | % of value | Quarter |
|---|---|---|---|---|
| Frazier Life Sciences Management, L.P. | 16,943,774 | $542M | 13.6% | 2026-Q1 |
| Capital World Investors added | 11,109,034 | $356M | 8.9% | 2026-Q1 |
| RA CAPITAL MANAGEMENT, L.P. | 9,550,191 | $306M | 7.7% | 2026-Q1 |
| FCPM III SERVICES B.V. | 9,198,900 | $294M | 7.4% | 2026-Q1 |
| FMR LLC added | 8,765,811 | $281M | 7.1% | 2026-Q1 |
| Bain Capital Life Sciences Investors, LLC | 7,306,566 | $234M | 5.9% | 2026-Q1 |
| WELLINGTON MANAGEMENT GROUP LLP trimmed | 5,030,124 | $161M | 4.0% | 2026-Q1 |
| DEERFIELD MANAGEMENT COMPANY, L.P. added | 4,264,789 | $137M | 3.4% | 2026-Q1 |
| VIKING GLOBAL INVESTORS LP | 4,203,567 | $135M | 3.4% | 2026-Q1 |
| Duquesne Family Office LLC | 3,070,146 | $98M | 2.5% | 2026-Q1 |
| Polar Capital Holdings Plc added | 2,831,607 | $91M | 2.3% | 2026-Q1 |
| JENNISON ASSOCIATES LLC trimmed | 2,750,403 | $88M | 2.2% | 2026-Q1 |
| Medicxi Ventures Management (Jersey) Ltd trimmed | 2,674,182 | $86M | 2.2% | 2026-Q1 |
| JANUS HENDERSON GROUP PLC trimmed | 2,258,984 | $72M | 1.8% | 2026-Q1 |
| WESTFIELD CAPITAL MANAGEMENT CO LP new | 2,202,913 | $71M | 1.8% | 2026-Q1 |
| MAVERICK CAPITAL LTD added | 2,186,402 | $70M | 1.8% | 2026-Q1 |
| GOLDMAN SACHS GROUP INC added | 1,946,374 | $62M | 1.6% | 2026-Q1 |
| Capital International Investors trimmed | 1,441,131 | $46M | 1.2% | 2026-Q1 |
| ALLIANCEBERNSTEIN L.P. trimmed | 1,199,325 | $42M | 1.1% | 2026-Q1 |
| ADAGE CAPITAL PARTNERS GP, L.L.C. trimmed | 1,106,631 | $35M | 0.9% | 2026-Q1 |
| Castle Hook Partners LP trimmed | 1,042,637 | $33M | 0.8% | 2026-Q1 |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. added | 957,442 | $31M | 0.8% | 2026-Q1 |
| Cormorant Asset Management, LP trimmed | 950,000 | $30M | 0.8% | 2026-Q1 |
| BlackRock, Inc. added | 886,616 | $28M | 0.7% | 2026-Q1 |
| BANK OF AMERICA CORP /DE/ added | 847,089 | $27M | 0.7% | 2026-Q1 |
| Aberdeen Group plc added | 837,005 | $27M | 0.7% | 2026-Q1 |
| JPMORGAN CHASE & CO trimmed | 884,228 | $26M | 0.7% | 2026-Q1 |
| UBS Group AG trimmed | 794,976 | $25M | 0.6% | 2026-Q1 |
| FRANKLIN RESOURCES INC added | 770,160 | $25M | 0.6% | 2026-Q1 |
| AMERIPRISE FINANCIAL INC added | 753,054 | $24M | 0.6% | 2026-Q1 |
| Woodline Partners LP added | 752,308 | $24M | 0.6% | 2026-Q1 |
| TimesSquare Capital Management, LLC trimmed | 751,988 | $24M | 0.6% | 2026-Q1 |
| CITADEL ADVISORS LLC added | 712,064 | $23M | 0.6% | 2026-Q1 |
| Logos Global Management LP added | 600,000 | $19M | 0.5% | 2026-Q1 |
| Rock Springs Capital Management LP added | 588,794 | $19M | 0.5% | 2026-Q1 |
| First Turn Management, LLC trimmed | 558,336 | $18M | 0.4% | 2026-Q1 |
| MORGAN STANLEY added | 555,761 | $18M | 0.4% | 2026-Q1 |
| AMERICAN CENTURY COMPANIES INC trimmed | 519,455 | $17M | 0.4% | 2026-Q1 |
| Artia Global Partners LP | 503,936 | $16M | 0.4% | 2026-Q1 |
| Handelsbanken Fonder AB added | 418,900 | $13M | 0.3% | 2026-Q1 |
| KENNEDY CAPITAL MANAGEMENT LLC added | 408,492 | $13M | 0.3% | 2026-Q1 |
| Bank of New York Mellon Corp trimmed | 378,800 | $12M | 0.3% | 2026-Q1 |
| Decheng Capital LLC trimmed | 325,057 | $10M | 0.3% | 2026-Q1 |
| Slate Path Capital LP | 319,000 | $10M | 0.3% | 2026-Q1 |
| MILLENNIUM MANAGEMENT LLC added | 303,848 | $10M | 0.2% | 2026-Q1 |
| Eversept Partners, LP trimmed | 285,764 | $9M | 0.2% | 2026-Q1 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC added | 285,285 | $9M | 0.2% | 2026-Q1 |
| Affinity Asset Advisors, LLC | 275,000 | $9M | 0.2% | 2026-Q1 |
| SEB Asset Management AB new | 272,654 | $9M | 0.2% | 2026-Q1 |
| FIRST TRUST ADVISORS LP trimmed | 267,105 | $9M | 0.2% | 2026-Q1 |
| MARSHALL WACE, LLP trimmed | 264,802 | $8M | 0.2% | 2026-Q1 |
| ArrowMark Colorado Holdings LLC trimmed | 259,524 | $8M | 0.2% | 2026-Q1 |
| Ensign Peak Advisors, Inc trimmed | 249,190 | $8M | 0.2% | 2026-Q1 |
| GILDER GAGNON HOWE & CO LLC trimmed | 241,475 | $8M | 0.2% | 2026-Q1 |
| LORD, ABBETT & CO. LLC trimmed | 195,355 | $6M | 0.2% | 2026-Q1 |
| STEMPOINT CAPITAL LP added | 180,658 | $6M | 0.1% | 2026-Q1 |
| PEREGRINE CAPITAL MANAGEMENT LLC new | 178,493 | $6M | 0.1% | 2026-Q1 |
| VICTORY CAPITAL MANAGEMENT INC new | 172,663 | $6M | 0.1% | 2026-Q1 |
| Atle Fund Management AB trimmed | 94,796 | $6M | 0.1% | 2026-Q1 |
| JANE STREET GROUP, LLC trimmed | 165,201 | $5M | 0.1% | 2026-Q1 |
| DCF Advisers, LLC | 160,600 | $5M | 0.1% | 2026-Q1 |
| XTX Topco Ltd added | 144,759 | $5M | 0.1% | 2026-Q1 |
| VANGUARD PORTFOLIO MANAGEMENT LLC new | 135,031 | $4M | 0.1% | 2026-Q1 |
| Nicholas Investment Partners, LP trimmed | 125,136 | $4M | 0.1% | 2026-Q1 |
| DEUTSCHE BANK AG\ added | 124,775 | $4M | 0.1% | 2026-Q1 |
| ADAR1 Capital Management, LLC | 118,623 | $4M | 0.1% | 2026-Q1 |
| Moody Aldrich Partners LLC trimmed | 114,975 | $4M | 0.1% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC added | 104,396 | $3M | 0.1% | 2026-Q1 |
| Swedbank AB added | 100,900 | $3M | 0.1% | 2026-Q1 |
| ALPS ADVISORS INC added | 93,596 | $3M | 0.1% | 2026-Q1 |
| Swiss National Bank | 88,900 | $3M | 0.1% | 2026-Q1 |
| Russell Investments Group, Ltd. added | 84,385 | $3M | 0.1% | 2026-Q1 |
| Catalio Capital Management, LP new | 83,554 | $3M | 0.1% | 2026-Q1 |
| STATE STREET CORP trimmed | 63,090 | $2M | 0.1% | 2026-Q1 |
| Walleye Capital LLC trimmed | 58,434 | $2M | 0.0% | 2026-Q1 |
| SEI INVESTMENTS CO added | 55,637 | $2M | 0.0% | 2026-Q1 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM added | 54,329 | $2M | 0.0% | 2026-Q1 |
| FRED ALGER MANAGEMENT, LLC added | 54,195 | $2M | 0.0% | 2026-Q1 |
| Mizuho Markets Cayman LP added | 52,227 | $2M | 0.0% | 2026-Q1 |
| DZ BANK AG Deutsche Zentral Genossenschafts Bank, Frankfurt am Main trimmed | 46,936 | $2M | 0.0% | 2026-Q1 |
| China Universal Asset Management Co., Ltd. added | 43,703 | $1M | 0.0% | 2026-Q1 |
| Squarepoint Ops LLC added | 43,021 | $1M | 0.0% | 2026-Q1 |
| BNP PARIBAS FINANCIAL MARKETS added | 37,450 | $1M | 0.0% | 2026-Q1 |
| Siren, L.L.C. trimmed | 765,705 | $22M | 0.5% | 2025-Q3 stale |
| Lisanti Capital Growth, LLC added | 179,410 | $6M | 0.2% | 2025-Q4 stale |
| VANGUARD GROUP INC added | 172,956 | $6M | 0.2% | 2025-Q4 stale |
| AXA Investment Managers S.A. new | 196,782 | $6M | 0.1% | 2025-Q3 stale |
| Cutter Capital Management, LP trimmed | 221,152 | $5M | 0.1% | 2025-Q1 stale |
| AXA S.A. added | 242,916 | $4M | 0.1% | 2025-Q2 stale |
| Saturn V Capital Management LP trimmed | 153,147 | $4M | 0.1% | 2025-Q3 stale |
| PRICE T ROWE ASSOCIATES INC /MD/ trimmed | 116,258 | $4M | 0.1% | 2025-Q4 stale |
| JTC Employer Solutions Trustee Ltd new | 75,500 | $3M | 0.1% | 2025-Q4 stale |
| Centiva Capital, LP new | 80,000 | $3M | 0.1% | 2025-Q4 stale |
| Parkman Healthcare Partners LLC added | 100,955 | $2M | 0.1% | 2025-Q1 stale |
| Jain Global LLC new | 47,584 | $2M | 0.0% | 2025-Q4 stale |
| Ikarian Capital, LLC trimmed | 45,830 | $2M | 0.0% | 2025-Q4 stale |
| Avidity Partners Management LP trimmed | 68,000 | $1M | 0.0% | 2025-Q1 stale |
| Trexquant Investment LP new | 66,102 | $1M | 0.0% | 2025-Q1 stale |
| ExodusPoint Capital Management, LP new | 59,644 | $1M | 0.0% | 2025-Q1 stale |
| BVF INC/IL trimmed | 59,065 | $1M | 0.0% | 2025-Q1 stale |
Ownership over time
Tracked institutional holder count and total shares held by filing quarter (independent scales). The curated-era tail and any mid-ingest latest quarter are handled honestly — a partial quarter is not drawn as a collapse.
Reading this table
Funds hold the same stock for different reasons — an index fund “holds” almost everything, an active manager sizes a name to a mandate and a benchmark, and each fund entered at its own price and time. Because 13F is filed up to 45 days after quarter-end, every row is a backward-looking snapshot; a manager may have traded since. Share-class siblings (a company’s A and C shares) are rolled up to one line so a dual-class name is never double-counted. Compare like-for-like. A large holder is not an endorsement, and a fund exiting is not a warning — this is a starting question, not a verdict.
About 13F filings
A Form 13F is a quarterly disclosure that institutional investment managers with over $100 million in US-listed equities must file with the SEC. In plain English: it is a snapshot of the long stock positions a fund held at the end of a quarter. It covers long US-listed equities only — not short positions, options, cash, or private holdings — and the funds shown are the large sample we track, not the complete 13F universe.