Mediaalpha Inc. Class AMAX
13F holders, Q3 2025 (September 30)At the end of Q3 2025, 157 institutions reported holding Mediaalpha Inc. Class A (MAX) in their 13F filings, up 5 from Q2 2025. 26 opened new positions and 20 sold out. The largest holders were White Mountains Insurance Group Ltd. ($203.2M), BlackRock, Inc. ($40.7M) and Vanguard Group Inc. ($29.6M). 5 famous investors held it, including Jim Simons / Peter Brown (0.0% of Renaissance Technologies's portfolio), Israel Englander (0.0% of Millennium Management's portfolio) and Cliff Asness (0.0% of AQR Capital Management's portfolio).
- Company
- Mediaalpha Inc. Class A
- CUSIP
- 58450V104
- Latest filing quarter
- Q2 2026
History
Number of 13F holders
Total Exit/New Position Q2 2025 → Q3 2025
| Institutions | Total Value | |
|---|---|---|
| New Positions | 26 | $10.1M |
| Exits | 20 | $13.2M |
All 13F filers, Q2 2025 → Q3 2025: 5,692,521 shares bought and 6,095,886 shares sold, net −403,365 shares. Counts holders who added, trimmed, opened or closed a position; split-adjusted.
Ownership 157 holders
| White Mountains Insurance Group Ltd. | 100.00% | No change | 17,856,614 | $203.2M |
| BlackRock, Inc. | 0.00% | Reduce -10.8% | 3,573,190 | $40.7M |
| Vanguard Group Inc. | 0.00% | Reduce -9.0% | 2,600,621 | $29.6M |
| Broad Bay Capital Management, LP | 2.08% | Reduce -41.2% | 1,468,695 | $16.7M |
| Millennium Management | 0.01% | Add +680.9% | 1,429,556 | $16.3M |
| Clearline Capital LP | 1.27% | Reduce -9.4% | 1,290,849 | $14.7M |
| Goldman Sachs Group Inc. | 0.00% | Reduce -36.2% | 1,279,960 | $14.6M |
| JPMorgan Chase & Co. | 0.00% | Add +95.2% | 1,058,441 | $12.0M |
| Renaissance Technologies | 0.01% | Add +22.4% | 945,100 | $10.8M |
| Morgan Stanley | 0.00% | Add +15.4% | 872,031 | $9.9M |
| Jacobs Asset Management, LLC | 5.10% | Add +2.5% | 819,026 | $9.3M |
| Shay Capital LLC | 1.63% | Add +17.9% | 790,100 | $9.0M |
| AQR Capital Management | 0.01% | Add +28.1% | 770,679 | $8.8M |
| Geode Capital Management, LLC | 0.00% | Add +0.7% | 769,774 | $8.8M |
| Victory Capital Management Inc. | 0.00% | Add +1261.9% | 710,819 | $8.1M |
| Nuveen, LLC | 0.00% | Reduce -23.4% | 690,465 | $7.9M |
| State Street Corp. | 0.00% | Add +3.0% | 672,126 | $7.6M |
| Jacobs Levy Equity Management, Inc. | 0.03% | Add +19.4% | 560,765 | $6.4M |
| J. Goldman & Co LP | 0.23% | Add +203.4% | 531,027 | $6.0M |
| Arrowstreet Capital, Limited Partnership | 0.00% | Add +7.5% | 520,452 | $5.9M |
| Qube Research & Technologies Ltd | 0.01% | Reduce -4.2% | 504,342 | $5.7M |
| D. E. Shaw & Co. | 0.00% | Reduce -49.2% | 454,883 | $5.2M |
| Acadian Asset Management LLC | 0.01% | Reduce -21.1% | 419,839 | $4.8M |
| Janus Henderson Group PLC | 0.00% | Reduce -39.0% | 386,155 | $4.4M |
| G2 Investment Partners Management LLC | 0.88% | New | 375,473 | $4.3M |
| Lighthouse Investment Partners, LLC | 0.15% | Add +831.7% | 353,930 | $4.0M |
| Franklin Resources Inc. | 0.00% | Add +1480.6% | 317,972 | $3.6M |
| Lazard Asset Management LLC | 0.00% | Reduce -24.4% | 294,796 | $3.4M |
| Northern Trust Corp. | 0.00% | Add +3.5% | 287,762 | $3.3M |
| Charles Schwab Investment Management Inc. | 0.00% | Reduce -10.2% | 279,734 | $3.2M |
| Algert Global LLC | 0.05% | Add +20.4% | 275,387 | $3.1M |
| Earnest Partners LLC | 0.01% | No change | 269,607 | $3.1M |
| Pacer Advisors, Inc. | 0.01% | Reduce -26.2% | 246,427 | $2.8M |
| Y-Intercept (Hong Kong) Ltd | 0.06% | Add +27.6% | 207,616 | $2.4M |
| BNP Paribas Financial Markets | 0.00% | Add +122.4% | 193,587 | $2.2M |
| Marshall Wace, LLP | 0.00% | Add +10.3% | 182,743 | $2.1M |
| Jane Street Group, LLC | 0.00% | New | 176,305 | $2.0M |
| PDT Partners, LLC | 0.12% | No change | 165,540 | $1.9M |
| UBS Group AG | 0.00% | Reduce -73.8% | 138,186 | $1.6M |
| Canada Pension Plan Investment Board | 0.00% | Add +4.2% | 130,600 | $1.5M |
| Dimensional Fund Advisors LP | 0.00% | Add +85.1% | 118,692 | $1.4M |
| Los Angeles Capital Management LLC | 0.00% | Reduce -12.5% | 104,580 | $1.2M |
| Bank of New York Mellon Corp | 0.00% | Add +4.3% | 99,144 | $1.1M |
| Divisadero Street Capital Management, LP | 0.05% | No change | 86,907 | $989K |
| Barclays PLC | 0.00% | Reduce -24.5% | 85,840 | $977K |
| Bank of America Corp. | 0.00% | Reduce -63.6% | 82,079 | $934K |
| Teacher Retirement System of Texas | 0.00% | Reduce -46.3% | 80,530 | $916K |
| Ieq Capital, LLC | 0.00% | Add +78.5% | 79,557 | $905K |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC | 0.00% | Reduce -42.4% | 71,458 | $813K |
| Boothbay Fund Management, LLC | 0.02% | New | 70,666 | $804K |
| Janney Montgomery Scott LLC | 0.00% | Reduce -13.9% | 70,355 | $801K |
| Allianz Asset Management GmbH | 0.00% | Reduce -0.1% | 70,176 | $799K |
| Blair William & Co. | 0.00% | Add +3.4% | 66,197 | $753K |
| Susquehanna International Group, LLP | 0.00% | Reduce -30.3% | 64,180 | $730K |
| Sei Investments Co. | 0.00% | Reduce -45.9% | 62,721 | $714K |
| Mariner, LLC | 0.00% | Add +30.4% | 61,909 | $705K |
| Swiss National Bank | 0.00% | No change | 58,700 | $668K |
| Rhumbline Advisers | 0.00% | Reduce -3.6% | 53,590 | $610K |
| Nomura Holdings Inc. | 0.00% | Add +35.8% | 52,965 | $603K |
| Russell Investments Group, Ltd. | 0.00% | Reduce -4.7% | 51,634 | $588K |
| State of Wyoming | 0.06% | Add +718.9% | 46,225 | $526K |
| Semanteon Capital Management, LP | 0.64% | Add +344.7% | 44,583 | $507K |
| Gotham Asset Management | 0.00% | Add +10.2% | 42,444 | $483K |
| Raymond James Financial Inc. | 0.00% | Add +629.1% | 41,408 | $471K |
| Verition Fund Management LLC | 0.00% | Reduce -4.5% | 41,253 | $469K |
| Alliancebernstein L.P. | 0.00% | No change | 38,630 | $440K |
| Quantbot Technologies LP | 0.01% | Add +87.5% | 38,615 | $439K |
| Allspring Global Investments Holdings, LLC | 0.00% | Reduce -1.0% | 39,195 | $438K |
| Cwm, LLC | 0.00% | Add +69.2% | 38,383 | $437K |
| Legal & General Group Plc | 0.00% | Reduce -6.6% | 33,934 | $386K |
| Voleon Capital Management LP | 0.01% | Add +77.8% | 32,090 | $365K |
| State of Wisconsin Investment Board | 0.00% | Reduce -63.2% | 31,191 | $355K |
| Jain Global LLC | 0.00% | New | 31,143 | $354K |
| Squarepoint Ops LLC | 0.00% | Reduce -47.7% | 30,658 | $349K |
| Deutsche Bank AG | 0.00% | Add +12.6% | 30,409 | $346K |
| California State Teachers Retirement System | 0.00% | Add +0.0% | 30,347 | $345K |
| Engineers Gate Manager LP | 0.00% | Reduce -56.5% | 30,058 | $342K |
| Universal- Beteiligungs- und Servicegesellschaft mbH | 0.00% | Reduce -13.7% | 29,864 | $340K |
| Dynamic Technology Lab Private Ltd | 0.06% | Add +170.5% | 29,237 | $333K |
| XTX Topco Ltd | 0.02% | Add +107.9% | 29,074 | $331K |
| T. Rowe Price Associates Inc. | 0.00% | Add +17.6% | 28,776 | $328K |
| Cerity Partners LLC | 0.00% | Add +37.7% | 27,644 | $315K |
| Prelude Capital Management, LLC | 0.02% | New | 26,892 | $306K |
| Cannell & Spears LLC | 0.01% | Reduce -34.3% | 25,700 | $292K |
| Principal Financial Group Inc. | 0.00% | New | 24,716 | $281K |
| FourThought Financial Partners, LLC | 0.02% | New | 24,691 | $281K |
| VIRGINIA RETIREMENT SYSTEMS ET Al | 0.00% | Add +22.5% | 24,500 | $279K |
| PharVision Advisers, LLC | 0.16% | New | 24,480 | $279K |
| SG Americas Securities, LLC | 0.00% | Add +131.0% | 24,038 | $274K |
| Axq Capital, LP | 0.10% | New | 23,144 | $263K |
| Two Sigma Investments, LP | 0.00% | Reduce -65.9% | 22,524 | $256K |
| MetLife Investment Management, LLC | 0.00% | No change | 21,402 | $244K |
| Wells Fargo & Company | 0.00% | Add +18.5% | 20,462 | $233K |
| Two Sigma Advisers, LP | 0.00% | Reduce -51.3% | 20,400 | $232K |
| Wealth Enhancement Advisory Services, LLC | 0.00% | Add +37.0% | 20,212 | $227K |
| Invesco Ltd. | 0.00% | Add +84.1% | 19,705 | $224K |
| Arax Advisory Partners | 0.00% | Add +1797.3% | 19,656 | $224K |
| Creative Planning | 0.00% | Add +27.4% | 19,529 | $222K |
| Royal Bank of Canada | 0.00% | Add +155.6% | 19,223 | $218K |
| Virtus Advisers, LLC | 0.12% | No change | 18,711 | $213K |
"% of holder's portfolio" is MAX's weight in each manager's 13F, not the share of Mediaalpha Inc. Class A the manager owns.