Ranked by reported Q1 2026 13F market value
Share of total reported institutional value in PBYI held by the largest 10 / 25 filers.
| # | Institution | Shares Held | Market Value | QoQ Change | Ownership % | % of Fund |
|---|---|---|---|---|---|---|
| 1 | ACORN CAPITAL ADVISORS, LLC | 4.1M | $26.4M | 0.0% | 8.117% | 7.50% |
| 2 | BlackRock, Inc. | 3.6M | $23.0M | -1.2% | 7.071% | 0.00% |
| 3 | RENAISSANCE TECHNOLOGIES LLC | 1.9M | $12.4M | -8.5% | 3.816% | 0.02% |
| 4 | AMERICAN CENTURY COMPANIES INC | 1.9M | $12.2M | +16.1% | 3.765% | 0.01% |
| 5 | VANGUARD CAPITAL MANAGEMENT LLC | 1.8M | $11.6M | — | 3.571% | 0.00% |
| 6 | VANGUARD PORTFOLIO MANAGEMENT LLC | 1.7M | $11.1M | — | 3.408% | 0.00% |
| 7 | MILLENNIUM MANAGEMENT LLC | 1.5M | $9.4M | +8793.2% | 2.903% | 0.01% |
| 8 | DIMENSIONAL FUND ADVISORS LP | 1.4M | $9.2M | +7.2% | 2.821% | 0.00% |
| 9 | O'SHAUGHNESSY ASSET MANAGEMENT, LLC | 1.1M | $7.3M | +1.6% | 2.236% | 0.04% |
| 10 | GEODE CAPITAL MANAGEMENT, LLC | 1.0M | $6.5M | +2.3% | 1.999% | 0.00% |
| 11 | STATE STREET CORP | 918K | $5.9M | +4.6% | 1.803% | 0.00% |
| 12 | KENNEDY CAPITAL MANAGEMENT, INC. | 890K | $5.7M | +2.5% | 1.748% | 0.12% |
| 13 | AQR CAPITAL MANAGEMENT LLC | 800K | $5.1M | +20.0% | 1.572% | 0.00% |
| 14 | Connor, Clark & Lunn Investment Management Ltd. | 783K | $5.0M | -10.6% | 1.538% | 0.01% |
| 15 | BRIDGEWAY CAPITAL MANAGEMENT, LLC | 775K | $5.0M | +0.2% | 1.523% | 0.10% |
| 16 | RITHOLTZ WEALTH MANAGEMENT | 774K | $4.9M | +11.6% | 1.521% | 0.09% |
| 17 | GOLDMAN SACHS GROUP INC | 670K | $4.3M | -15.7% | 1.316% | 0.00% |
| 18 | NORTHERN TRUST CORP | 642K | $4.1M | +4.2% | 1.261% | 0.00% |
| 19 | ARROWSTREET CAPITAL, LIMITED PARTNERSHIP | 538K | $3.4M | -1.8% | 1.057% | 0.00% |
| 20 | UBS Group AG | 534K | $3.4M | +319.6% | 1.050% | 0.00% |
| 21 | SEI INVESTMENTS CO | 508K | $3.2M | +18.2% | 0.998% | 0.00% |
| 22 | MORGAN STANLEY | 360K | $2.3M | +10.1% | 0.707% | 0.00% |
| 23 | D. E. Shaw & Co., Inc. | 351K | $2.2M | -7.1% | 0.690% | 0.00% |
| 24 | GLOBEFLEX CAPITAL L P | 350K | $2.2M | -22.8% | 0.687% | 0.34% |
| 25 | Bank of New York Mellon Corp | 348K | $2.2M | -1.1% | 0.683% | 0.00% |
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 PBYI — a direct measure of their conviction.
Filings activity in PBYI during Q1 2026, grouped by how each filer changed its position.
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 | 154 | +2.0% | 58.94% | +6.63 pp | $220M | +13% |
| Q4 2025 | 151 | +16% | 52.31% | +7.20 pp | $195M | +16% |
| Q3 2025 | 130 | +7.4% | 45.11% | +17.89 pp | $168M | +66% |
| Q2 2025 | 121 | +3.4% | 27.22% | +4.90 pp | $102M | +22% |
| Q1 2025 | 117 | +7.3% | 22.32% | +0.44 pp | $83M | +2.0% |
| Q4 2024 | 109 | +7.9% | 21.88% | 66.94 pp | $82M | 75% |
| Q3 2024 | 101 | +2.0% | 88.82% | +63.77 pp | $331M | +255% |
| Q2 2024 | 99 | — | 25.05% | — | $93M | — |
Source: SEC 13F institutional filings. Ownership % requires market cap data and will show once linked. Δ columns compare to the immediately prior filed quarter.
Quick answers to the most common questions about buying PBYI stock.
Based on Q1 2026 13F filings, institutional ownership of Puma Biotechnology, Inc. stands at 58.9%, held across 154 reporting institutions.
ACORN CAPITAL ADVISORS, LLC is the largest reported institutional holder of PBYI, with approximately 4,131,299 shares worth $0.03B as of Q1 2026.
Yes — 2 widely-followed marquee investors appear among the top 25 institutional holders of PBYI, including RENAISSANCE TECHNOLOGIES LLC, MILLENNIUM MANAGEMENT LLC.
Our composite Smart Money Score for PBYI is 66 out of 100 (Bullish). It combines net institutional buying activity, ownership shift, marquee investor presence, and holder-count growth.
28 institutions opened new positions in PBYI during Q1 2026, while 25 fully exited. 94 added to existing positions and 29 trimmed.
PBYI institutional ownership rose by 6.63 percentage points quarter-over-quarter, with a net change of +3 holders.
The top 10 institutions account for 58.7% of all reported 13F value in PBYI, and the top 25 account for 85.6%.
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.
Puma Biotechnology, Inc. (PBYI) Institutional Ownership