Who owns PubMatic (PUBM)
Which tracked institutional funds hold PUBM, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See PUBM company fundamentals →
Ownership as of the 2026-Q2 13F filings (latest filed 2026-09-22). 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
The tracked-fund tape on PUBM is one-sided between 2026-Q1 and 2026-Q2: 61 added or opened and 9 trimmed or exited — on balance accumulating.
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
PUBM’s largest tracked holder by dollar value, BlackRock, Inc., sizes it at 0.0% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 0.0pp gap the other way — the median holder sizes PUBM more heavily than its largest holder by dollar value does.
Book-share is each fund’s reported value in PUBM 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 2026-Q1 and 2026-Q2, across 148 tracked filers holding PUBM, 77 increased or opened the position and 69 reduced or closed it; over the same quarter, open-market insider Form 4s were net sales.
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 PUBM between the 2026-Q1 and 2026-Q2 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 6
- HIGHBRIDGE CAPITAL MANAGEMENT LLC$8M
- BOOTHBAY FUND MANAGEMENT, LLC$2M
- Jump Financial, LLC$1M
- Walleye Capital LLC$831K
- Inspire Investing, LLC$678K
- RAYMOND JAMES FINANCIAL INC$563K
Full exits 6
- Graham Holdings Co$28M
- ACADIAN ASSET MANAGEMENT LLC$13M
- TUDOR INVESTMENT CORP ET AL$3M
- Man Group plc$963K
- GSA CAPITAL PARTNERS LLP$728K
- Cardinal Point Capital Management ULC$585K
Largest adds
- BlackRock, Inc.$18M
- DIMENSIONAL FUND ADVISORS LP$9M
- Whitefort Capital Management, LP$9M
- VANGUARD CAPITAL MANAGEMENT LLC$9M
- AMERICAN CENTURY COMPANIES INC$8M
- VANGUARD PORTFOLIO MANAGEMENT LLC$7M
Largest trims
- CenterBook Partners LP$9M
- D. E. Shaw & Co., Inc.$3M
- Brevan Howard Capital Management LP$324K
Institutional holders
One row per tracked fund, most shares held first (every row is from one quarter; reported value breaks ties). “% of value” is the fund’s share of this security’s tracked institutional value — not of shares outstanding.
| Fund | Shares | Reported value | % of value | Quarter |
|---|---|---|---|---|
| BlackRock, Inc. added | 3,279,530 | $43M | 12.9% | 2026-Q2 |
| VANGUARD CAPITAL MANAGEMENT LLC added | 1,661,312 | $22M | 6.6% | 2026-Q2 |
| DIMENSIONAL FUND ADVISORS LP added | 1,491,121 | $20M | 5.9% | 2026-Q2 |
| RENAISSANCE TECHNOLOGIES LLC trimmed | 1,421,049 | $19M | 5.6% | 2026-Q2 |
| Whitefort Capital Management, LP added | 1,110,656 | $15M | 4.4% | 2026-Q2 |
| GEODE CAPITAL MANAGEMENT, LLC added | 991,800 | $13M | 3.9% | 2026-Q2 |
| VANGUARD PORTFOLIO MANAGEMENT LLC added | 947,548 | $12M | 3.7% | 2026-Q2 |
| JACOBS LEVY EQUITY MANAGEMENT, INC trimmed | 862,996 | $11M | 3.4% | 2026-Q2 |
| STATE STREET CORP added | 854,147 | $11M | 3.4% | 2026-Q2 |
| S SQUARED TECHNOLOGY, LLC added | 748,099 | $10M | 3.0% | 2026-Q2 |
| Simcoe Capital LLC added | 693,903 | $9M | 2.7% | 2026-Q2 |
| HIGHBRIDGE CAPITAL MANAGEMENT LLC new | 644,593 | $8M | 2.5% | 2026-Q2 |
| AMERICAN CENTURY COMPANIES INC added | 642,076 | $8M | 2.5% | 2026-Q2 |
| TWO SIGMA INVESTMENTS, LP added | 638,102 | $8M | 2.5% | 2026-Q2 |
| ROYAL BANK OF CANADA trimmed | 619,290 | $8M | 2.4% | 2026-Q2 |
| Nuveen, LLC added | 464,187 | $6M | 1.8% | 2026-Q2 |
| CITADEL ADVISORS LLC added | 414,880 | $5M | 1.6% | 2026-Q2 |
| CenterBook Partners LP trimmed | 413,983 | $5M | 1.6% | 2026-Q2 |
| Trexquant Investment LP trimmed | 382,525 | $5M | 1.5% | 2026-Q2 |
| NORTHERN TRUST CORP added | 348,134 | $5M | 1.4% | 2026-Q2 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 303,624 | $4M | 1.2% | 2026-Q2 |
| PANAGORA ASSET MANAGEMENT INC added | 287,735 | $4M | 1.1% | 2026-Q2 |
| AQR CAPITAL MANAGEMENT LLC added | 286,438 | $4M | 1.1% | 2026-Q2 |
| MORGAN STANLEY trimmed | 284,256 | $4M | 1.1% | 2026-Q2 |
| Quantinno Capital Management LP added | 249,688 | $3M | 1.0% | 2026-Q2 |
| VANGUARD FIDUCIARY TRUST CO added | 240,677 | $3M | 1.0% | 2026-Q2 |
| GOLDMAN SACHS GROUP INC trimmed | 240,578 | $3M | 0.9% | 2026-Q2 |
| JPMORGAN CHASE & CO trimmed | 224,952 | $3M | 0.9% | 2026-Q2 |
| FRANKLIN RESOURCES INC added | 223,316 | $3M | 0.9% | 2026-Q2 |
| JANE STREET GROUP, LLC trimmed | 199,131 | $3M | 0.8% | 2026-Q2 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP trimmed | 195,563 | $3M | 0.8% | 2026-Q2 |
| UBS Group AG added | 186,033 | $2M | 0.7% | 2026-Q2 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP trimmed | 182,447 | $2M | 0.7% | 2026-Q2 |
| BOOTHBAY FUND MANAGEMENT, LLC added | 181,615 | $2M | 0.7% | 2026-Q2 |
| BRIDGEWAY CAPITAL MANAGEMENT, LLC | 175,300 | $2M | 0.7% | 2026-Q2 |
| BANK OF AMERICA CORP /DE/ added | 173,956 | $2M | 0.7% | 2026-Q2 |
| Pinnacle Holdings, LLC added | 158,250 | $2M | 0.6% | 2026-Q2 |
| P.A.W. CAPITAL CORP trimmed | 150,000 | $2M | 0.6% | 2026-Q2 |
| Diversified Investment Strategies, LLC | 140,000 | $2M | 0.6% | 2026-Q2 |
| AMERIPRISE FINANCIAL INC | 134,001 | $2M | 0.5% | 2026-Q2 |
| Bank of New York Mellon Corp added | 121,540 | $2M | 0.5% | 2026-Q2 |
| Invesco Ltd. trimmed | 103,232 | $1M | 0.4% | 2026-Q2 |
| Jump Financial, LLC new | 100,612 | $1M | 0.4% | 2026-Q2 |
| DEUTSCHE BANK AG\ added | 93,716 | $1M | 0.4% | 2026-Q2 |
| MILLENNIUM MANAGEMENT LLC trimmed | 86,059 | $1M | 0.3% | 2026-Q2 |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. trimmed | 85,805 | $1M | 0.3% | 2026-Q2 |
| VICTORY CAPITAL MANAGEMENT INC added | 84,859 | $1M | 0.3% | 2026-Q2 |
| Russell Investments Group, Ltd. added | 83,628 | $1M | 0.3% | 2026-Q2 |
| Point72 Asset Management, L.P. added | 79,362 | $1M | 0.3% | 2026-Q2 |
| GROUP ONE TRADING LLC added | 72,405 | $950K | 0.3% | 2026-Q2 |
| PUBLIC EMPLOYEES RETIREMENT SYSTEM OF OHIO | 66,426 | $872K | 0.3% | 2026-Q2 |
| Walleye Capital LLC trimmed | 63,342 | $831K | 0.3% | 2026-Q2 |
| Squarepoint Ops LLC added | 62,137 | $815K | 0.2% | 2026-Q2 |
| SIMPLEX TRADING, LLC added | 59,051 | $775K | 0.2% | 2026-Q2 |
| BARCLAYS PLC trimmed | 59,016 | $774K | 0.2% | 2026-Q2 |
| CANADA PENSION PLAN INVESTMENT BOARD trimmed | 58,500 | $768K | 0.2% | 2026-Q2 |
| HSBC HOLDINGS PLC trimmed | 57,318 | $749K | 0.2% | 2026-Q2 |
| Creative Planning added | 57,143 | $750K | 0.2% | 2026-Q2 |
| Avestar Capital, LLC | 55,000 | $722K | 0.2% | 2026-Q2 |
| VOYA INVESTMENT MANAGEMENT LLC trimmed | 53,085 | $696K | 0.2% | 2026-Q2 |
| Inspire Investing, LLC added | 51,670 | $678K | 0.2% | 2026-Q2 |
| IMC-Chicago, LLC added | 50,081 | $657K | 0.2% | 2026-Q2 |
| RHUMBLINE ADVISERS trimmed | 49,564 | $650K | 0.2% | 2026-Q2 |
| State of Wyoming added | 45,405 | $596K | 0.2% | 2026-Q2 |
| D. E. Shaw & Co., Inc. trimmed | 44,320 | $581K | 0.2% | 2026-Q2 |
| RAYMOND JAMES FINANCIAL INC added | 42,900 | $563K | 0.2% | 2026-Q2 |
| STRS OHIO added | 38,000 | $499K | 0.2% | 2026-Q2 |
| FULLER & THALER ASSET MANAGEMENT, INC. trimmed | 36,441 | $478K | 0.1% | 2026-Q2 |
| ALLIANCEBERNSTEIN L.P. | 36,200 | $296K | 0.1% | 2026-Q2 |
| XTX Topco Ltd trimmed | 33,501 | $440K | 0.1% | 2026-Q2 |
| WELLS FARGO & COMPANY/MN trimmed | 32,904 | $432K | 0.1% | 2026-Q2 |
| PRICE T ROWE ASSOCIATES INC /MD/ added | 32,040 | $421K | 0.1% | 2026-Q2 |
| LOS ANGELES CAPITAL MANAGEMENT LLC added | 28,268 | $371K | 0.1% | 2026-Q2 |
| Allworth Financial LP added | 25,719 | $337K | 0.1% | 2026-Q2 |
| MetLife Investment Management, LLC | 24,504 | $321K | 0.1% | 2026-Q2 |
| MERCER GLOBAL ADVISORS INC /ADV added | 24,381 | $320K | 0.1% | 2026-Q2 |
| Cambria Investment Management, L.P. new | 22,828 | $300K | 0.1% | 2026-Q2 |
| Cornerstone Investment Partners, LLC new | 22,630 | $297K | 0.1% | 2026-Q2 |
| GWN SECURITIES INC. trimmed | 22,119 | $290K | 0.1% | 2026-Q2 |
| Sterling Capital Management LLC added | 21,457 | $282K | 0.1% | 2026-Q2 |
| Caption Management, LLC new | 20,950 | $275K | 0.1% | 2026-Q2 |
| CITIGROUP INC added | 20,768 | $272K | 0.1% | 2026-Q2 |
| MEEDER ASSET MANAGEMENT INC trimmed | 19,416 | $255K | 0.1% | 2026-Q2 |
| IEQ CAPITAL, LLC new | 18,913 | $248K | 0.1% | 2026-Q2 |
| Focus Partners Wealth added | 17,830 | $234K | 0.1% | 2026-Q2 |
| DIVERSIFIED TRUST CO | 17,564 | $230K | 0.1% | 2026-Q2 |
| BALYASNY ASSET MANAGEMENT L.P. trimmed | 17,416 | $228K | 0.1% | 2026-Q2 |
| SEI INVESTMENTS CO added | 16,977 | $223K | 0.1% | 2026-Q2 |
| WINTON GROUP Ltd added | 16,900 | $222K | 0.1% | 2026-Q2 |
| Grantham, Mayo, Van Otterloo & Co. LLC new | 15,974 | $210K | 0.1% | 2026-Q2 |
| Mariner, LLC new | 15,109 | $198K | 0.1% | 2026-Q2 |
| Jasper Ridge Partners, L.P. | 15,032 | $197K | 0.1% | 2026-Q2 |
| WEALTH ENHANCEMENT ADVISORY SERVICES, LLC new | 14,545 | $197K | 0.1% | 2026-Q2 |
| OCCUDO QUANTITATIVE STRATEGIES LP new | 13,371 | $175K | 0.1% | 2026-Q2 |
| Police & Firemen's Retirement System of New Jersey | 12,458 | $163K | 0.0% | 2026-Q2 |
| STATE BOARD OF ADMINISTRATION OF FLORIDA RETIREMENT SYSTEM | 12,430 | $163K | 0.0% | 2026-Q2 |
| Cetera Investment Advisers trimmed | 12,059 | $158K | 0.0% | 2026-Q2 |
| NEW YORK STATE COMMON RETIREMENT FUND | 11,752 | $154K | 0.0% | 2026-Q2 |
| Walleye Trading LLC trimmed | 11,560 | $152K | 0.0% | 2026-Q2 |
| Vanguard Global Advisers, LLC trimmed | 11,499 | $151K | 0.0% | 2026-Q2 |
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.