Puma Biotechnology, Inc. (PBYI) Ownership
PBYI ownership summary
as of October 18, 2026- Institutions
- 75.6% of shares outstanding
- Insiders
- 15.37% of shares outstanding
- Shares outstanding
- 51.6M
- Float
- 40.3M shares available to trade
- Short interest
- 9.68% 4.3M shares short
- Days to cover
- 13.84 short interest down 1.3% vs prior month
- Institutions 75.57%
- Insiders 15.37%
- Other investors 9.07%
PBYI top institutional holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | BlackRock Inc | 7.37% | 3.8M | $37.4M | +205,784 (+5.7%) | June 30, 2026 |
| 2 | American Century Companies Inc | 4.49% | 2.3M | $22.8M | +403,650 (+21.1%) | June 30, 2026 |
| 3 | Acadian Asset Management LLC | 3.98% | 2.1M | $20.2M | +11,764 (+0.6%) | June 30, 2026 |
| 4 | Renaissance Technologies Corp | 3.56% | 1.8M | $18.0M | −106,200 (−5.5%) | June 30, 2026 |
| 5 | Vanguard Capital Management, LLC | 3.56% | 1.8M | $18.0M | +17,962 (+1.0%) | June 30, 2026 |
| 6 | Vanguard Portfolio Management, LLC | 3.54% | 1.8M | $17.9M | +90,950 (+5.2%) | June 30, 2026 |
| 7 | LSV Asset Management | 3.13% | 1.6M | $15.9M | +435,113 (+36.8%) | June 30, 2026 |
| 8 | Dimensional Fund Advisors, Inc. | 2.94% | 1.5M | $14.9M | +81,908 (+5.7%) | June 30, 2026 |
| 9 | Geode Capital Management, LLC | 2.59% | 1.3M | $13.2M | +322,063 (+31.7%) | June 30, 2026 |
| 10 | O'Shaughnessy Asset Management LLC | 2.18% | 1.1M | $11.0M | −14,386 (−1.3%) | June 30, 2026 |
| 11 | State Street Corp | 1.84% | 952K | $9.4M | +34,575 (+3.8%) | June 30, 2026 |
| 12 | Kennedy Capital Management Inc | 1.69% | 873K | $8.6M | −16,348 (−1.8%) | June 30, 2026 |
| 13 | Bridgeway Capital Management, LLC | 1.53% | 792K | $7.8M | +16,275 (+2.1%) | June 30, 2026 |
| 14 | Comprehensive Portfolio Management, LLC | 1.45% | 750K | $7.4M | −24,510 (−3.2%) | June 30, 2026 |
| 15 | AQR Capital Management LLC | 1.40% | 725K | $7.1M | −75,002 (−9.4%) | June 30, 2026 |
| 16 | The Goldman Sachs Group Inc | 1.30% | 669K | $6.6M | −563 (−0.1%) | June 30, 2026 |
| 17 | Northern Trust Corp | 1.26% | 652K | $6.4M | +10,633 (+1.7%) | June 30, 2026 |
| 18 | Connor Clark & Lunn Inv Mgmt Ltd | 1.25% | 643K | $6.3M | −139,852 (−17.9%) | June 30, 2026 |
| 19 | UBS Group AG | 1.23% | 637K | $6.3M | +102,534 (+19.2%) | June 30, 2026 |
| 20 | Millennium Management LLC | 1.17% | 602K | $5.9M | −875,279 (−59.2%) | June 30, 2026 |
Value at the latest close. Change = shares bought or sold in the latest quarterly filing (13F). In the top 20, 12 holders added 1.7M shares and 8 cut 1.3M.
PBYI top mutual fund and ETF holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | Avantis US Small Cap Value ETF | 4.63% | 2.4M | $23.5M | +4,200 (+0.2%) | September 30, 2026 |
| 2 | Vanguard MStar Total Stk Mkt Idx Invest | 2.60% | 1.3M | $13.2M | — | August 31, 2026 |
| 3 | iShares Russell 2000 ETF | 2.29% | 1.2M | $11.6M | −13,632 (−1.1%) | September 30, 2026 |
| 4 | Vanguard Explorer Inv | 1.51% | 777K | $7.6M | — | June 30, 2026 |
| 5 | Vanguard Strategic Equity Inv | 1.05% | 540K | $5.3M | — | June 30, 2026 |
| 6 | Fidelity Small Cap Index | 0.94% | 484K | $4.8M | +6,056 (+1.3%) | July 31, 2026 |
| 7 | iShares Russell 2000 Value ETF | 0.70% | 362K | $3.6M | +548 (+0.2%) | September 30, 2026 |
| 8 | Northern Small Cap Value | 0.52% | 268K | $2.6M | — | June 30, 2026 |
| 9 | Vanguard Russell 2000 ETF | 0.50% | 257K | $2.5M | +2,818 (+1.1%) | September 30, 2026 |
| 10 | Russell Inv Tax-Managed US Mid&Sm Cap S | 0.48% | 248K | $2.4M | — | August 31, 2026 |
| 11 | EA Bridgeway Omni Small-Cap Value ETF | 0.47% | 243K | $2.4M | — | September 30, 2026 |
| 12 | DFA US Targeted Value I | 0.46% | 236K | $2.3M | +14,652 (+6.6%) | August 31, 2026 |
| 13 | EA Bridgeway Select Small-Cap Value ETF | 0.45% | 231K | $2.3M | — | September 30, 2026 |
| 14 | Invesco Dorsey Wright SmallCap Momt ETF | 0.45% | 231K | $2.3M | −615 (−0.3%) | September 30, 2026 |
| 15 | DFA US Small Cap I | 0.43% | 221K | $2.2M | — | August 31, 2026 |
| 16 | Fidelity Enhanced Small Cap Core ETF | 0.41% | 212K | $2.1M | +441 (+0.2%) | September 30, 2026 |
| 17 | BlackRock Advantage Small Cap Core Instl | 0.40% | 206K | $2.0M | — | August 31, 2026 |
| 18 | LSV Small Cap Value Institutional | 0.39% | 202K | $2.0M | +43,264 (+27.3%) | September 30, 2026 |
| 19 | Bridgeway Ultra-Small Company | 0.34% | 173K | $1.7M | — | June 30, 2026 |
| 20 | First Trust Dow Jones Sel MicroCap ETF | 0.33% | 172K | $1.7M | — | September 30, 2026 |
Funds report holdings monthly or quarterly; dates differ by fund.
PBYI insider transactions
latest 16| Date | Name | Transaction | Price | Shares | Value |
|---|---|---|---|---|---|
| 2026-01-07 | Alan H Auerbach | Sell | $5.88 | 18,012 | $105,911 |
| 2026-01-07 | Douglas M Hunt | Sell | $5.88 | 5,014 | $29,482 |
| 2026-01-06 | Alan H Auerbach | Sell | $5.84 | 16,938 | $98,918 |
| 2026-01-06 | Douglas M Hunt | Sell | $5.84 | 3,973 | $23,202 |
| 2025-11-11 | Michael Patrick Miller | Sell | $4.86 | 20,000 | $97,200 |
| 2025-07-18 | Alessandra Cesano | Sell | $3.37 | 27,000 | $90,990 |
| 2025-07-09 | Alan H Auerbach | Sell | $3.54 | 21,580 | $76,393 |
| 2025-07-09 | Douglas M Hunt | Sell | $3.54 | 3,443 | $12,188 |
| 2025-07-08 | Alan H Auerbach | Sell | $3.53 | 25,592 | $90,340 |
| 2025-07-08 | Douglas M Hunt | Sell | $3.53 | 4,374 | $15,440 |
| 2025-06-13 | Adrian Senderowicz | Sell | $3.40 | 27,000 | $91,800 |
| 2025-06-13 | Alessandra Cesano | Sell | $3.40 | 12,150 | $41,310 |
| 2025-06-13 | Allison Dorval | Sell | $3.40 | 11,610 | $39,474 |
| 2025-06-13 | Brian M Stuglik | Sell | $3.39 | 8,100 | $27,459 |
| 2025-06-13 | Jay M Moyes | Sell | $3.40 | 22,000 | $74,800 |
| 2025-06-13 | Troy Edward Wilson | Sell | $3.40 | 10,800 | $36,720 |
Reported trades by company officers, directors and other filers (including disclosures by members of Congress where EODHD lists them). "—" where the filing gives no share count.
PBYI shares outstanding
Year-end shares outstanding, adjusted for splits.
Who owns PBYI
Institutional investors own 75.6% of Puma Biotechnology's shares and insiders 15.37%. The largest holder is BlackRock Inc with 7.37% of the shares (3.8M), as of June 30, 2026. Among the top 20 institutions, 12 added shares and 8 reduced their stake in the latest filings. Short interest is 9.68% of the float, or 13.84 days of average trading volume. The share count rose 70.4% since 2014.
Related: PBYI analyst forecast, PBYI key metrics. See the PBYI stock overview for the latest quote and news.
PBYI ownership FAQ
Who owns the most Puma Biotechnology stock?
The largest shareholders of Puma Biotechnology are BlackRock Inc (7.37%), American Century Companies Inc (4.49%), Acadian Asset Management LLC (3.98%), Renaissance Technologies Corp (3.56%), Vanguard Capital Management, LLC (3.56%).
What percentage of Puma Biotechnology is owned by institutions?
Institutions hold 75.6% of Puma Biotechnology's shares outstanding; insiders hold 15.37%.
Which funds own Puma Biotechnology?
The largest fund holders of Puma Biotechnology are Avantis US Small Cap Value ETF (4.63%), Vanguard MStar Total Stk Mkt Idx Invest (2.60%), iShares Russell 2000 ETF (2.29%), Vanguard Explorer Inv (1.51%), Vanguard Strategic Equity Inv (1.05%).
What is Puma Biotechnology's short interest?
4.3M shares of Puma Biotechnology were sold short, 9.68% of the float; at the average daily volume it would take 13.84 days to cover.
Are insiders buying or selling Puma Biotechnology?
Of the latest 16 reported insider transactions in Puma Biotechnology (since June 13, 2025), 0 were purchases and 16 were sales.
How many shares of Puma Biotechnology are outstanding?
Puma Biotechnology has 51.6M shares outstanding, of which 40.3M are in the public float.