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Institutional Ownership · SEC Form 13F

Who owns MediaAlpha (MAX)


Which tracked institutional funds hold MAX, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See MAX 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.

148
Institutional holders
47M
Shares held (tracked funds)

How the tape is positioned

45 tracked funds added or opened MAX while 16 trimmed or exited it between 2026-Q1 and 2026-Q2 — 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

MAX’s largest tracked holder by dollar value, WHITE MOUNTAINS INSURANCE GROUP LTD, sizes it at 57.0% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 57.0pp conviction gap — its largest holder concentrates the name more heavily than the typical one.

Book-share is each fund’s reported value in MAX 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 MAX, 64 increased or opened the position and 102 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 MAX 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 5

  • EVR Research LP$6M
  • STIFEL FINANCIAL CORP$2M
  • Walleye Capital LLC$1M
  • WINMILL & CO. INC$818K
  • Hillsdale Investment Management Inc.$577K

Full exits 7

  • Pacer Advisors, Inc.$8M
  • ACADIAN ASSET MANAGEMENT LLC$8M
  • Philadelphia Financial Management of San Francisco, LLC$4M
  • HRT FINANCIAL LP$3M
  • Y-Intercept (Hong Kong) Ltd$1M
  • GSA CAPITAL PARTNERS LLP$1M

Largest adds

  • WHITE MOUNTAINS INSURANCE GROUP LTD$58M
  • Divisadero Street Capital Management, LP$12M
  • BlackRock, Inc.$10M
  • Clearline Capital LP$10M
  • JPMORGAN CHASE & CO$7M
  • CITADEL ADVISORS LLC$5M

Largest trims

  • Triad Investment Management$5M
  • J. Goldman & Co LP$3M
  • Qube Research & Technologies Ltd$3M
  • FRANKLIN RESOURCES INC$2M
  • SUSQUEHANNA INTERNATIONAL GROUP, LLP$1M
  • UBS Group AG$1M

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.

FundSharesReported value% of valueQuarter
WHITE MOUNTAINS INSURANCE GROUP LTD17,856,614$224M38.0%2026-Q2
BlackRock, Inc. trimmed3,392,357$43M7.2%2026-Q2
Clearline Capital LP added2,713,890$34M5.8%2026-Q2
JPMORGAN CHASE & CO added1,880,062$23M3.9%2026-Q2
VANGUARD CAPITAL MANAGEMENT LLC trimmed1,276,369$16M2.7%2026-Q2
GEODE CAPITAL MANAGEMENT, LLC trimmed1,068,308$13M2.3%2026-Q2
Divisadero Street Capital Management, LP added1,019,988$13M2.2%2026-Q2
JACOBS LEVY EQUITY MANAGEMENT, INC added971,232$12M2.1%2026-Q2
JACOBS ASSET MANAGEMENT, LLC trimmed919,761$12M2.0%2026-Q2
STATE STREET CORP added862,235$11M1.8%2026-Q2
ARROWSTREET CAPITAL, LIMITED PARTNERSHIP trimmed829,958$10M1.8%2026-Q2
MORGAN STANLEY added821,170$10M1.7%2026-Q2
Nuveen, LLC added752,447$9M1.6%2026-Q2
DIMENSIONAL FUND ADVISORS LP added701,914$9M1.5%2026-Q2
J. Goldman & Co LP trimmed598,070$8M1.3%2026-Q2
CITADEL ADVISORS LLC added589,696$7M1.3%2026-Q2
RENAISSANCE TECHNOLOGIES LLC trimmed574,407$7M1.2%2026-Q2
Shay Capital LLC trimmed570,000$7M1.2%2026-Q2
JANE STREET GROUP, LLC added551,625$7M1.2%2026-Q2
D. E. Shaw & Co., Inc. added535,926$7M1.1%2026-Q2
SPEECE THORSON CAPITAL GROUP INC trimmed489,098$6M1.0%2026-Q2
EVR Research LP new440,000$6M0.9%2026-Q2
VANGUARD PORTFOLIO MANAGEMENT LLC trimmed433,046$5M0.9%2026-Q2
GOLDMAN SACHS GROUP INC trimmed428,866$5M0.9%2026-Q2
TWO SIGMA INVESTMENTS, LP added409,480$5M0.9%2026-Q2
AQR CAPITAL MANAGEMENT LLC trimmed391,641$5M0.8%2026-Q2
BANK OF AMERICA CORP /DE/ added371,840$5M0.8%2026-Q2
Triad Investment Management trimmed368,731$5M0.8%2026-Q2
Stoic Point Capital Management LLC added297,150$4M0.6%2026-Q2
NORTHERN TRUST CORP trimmed267,107$3M0.6%2026-Q2
CHARLES SCHWAB INVESTMENT MANAGEMENT INC trimmed259,224$3M0.6%2026-Q2
Squarepoint Ops LLC added234,255$3M0.5%2026-Q2
VANGUARD FIDUCIARY TRUST CO trimmed223,917$3M0.5%2026-Q2
TEACHER RETIREMENT SYSTEM OF TEXAS added216,405$3M0.5%2026-Q2
ALLIANCEBERNSTEIN L.P. added211,450$2M0.3%2026-Q2
BNP PARIBAS FINANCIAL MARKETS added209,204$3M0.4%2026-Q2
UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC trimmed180,171$2M0.4%2026-Q2
XTX Topco Ltd added172,269$2M0.4%2026-Q2
ALGERT GLOBAL LLC added170,870$2M0.4%2026-Q2
Man Group plc added156,754$2M0.3%2026-Q2
PRINCIPAL FINANCIAL GROUP INC added148,845$2M0.3%2026-Q2
Quantinno Capital Management LP added136,034$2M0.3%2026-Q2
Russell Investments Group, Ltd. added130,360$2M0.3%2026-Q2
STIFEL FINANCIAL CORP new126,175$2M0.3%2026-Q2
VICTORY CAPITAL MANAGEMENT INC added101,365$1M0.2%2026-Q2
BALYASNY ASSET MANAGEMENT L.P. trimmed101,046$1M0.2%2026-Q2
Qube Research & Technologies Ltd trimmed92,453$1M0.2%2026-Q2
PDT Partners, LLC trimmed84,022$1M0.2%2026-Q2
Bank of New York Mellon Corp trimmed81,504$1M0.2%2026-Q2
Walleye Capital LLC added80,306$1M0.2%2026-Q2
FRANKLIN RESOURCES INC trimmed74,587$938K0.2%2026-Q2
STATE OF WISCONSIN INVESTMENT BOARD trimmed70,309$884K0.1%2026-Q2
Allianz Asset Management GmbH70,176$653K0.1%2026-Q2
WINMILL & CO. INC new65,102$818K0.1%2026-Q2
Swiss National Bank added60,800$764K0.1%2026-Q2
BLAIR WILLIAM & CO/IL added56,046$704K0.1%2026-Q2
GLOBEFLEX CAPITAL L P trimmed55,850$702K0.1%2026-Q2
Campbell & CO Investment Adviser LLC added46,617$586K0.1%2026-Q2
RHUMBLINE ADVISERS trimmed45,932$577K0.1%2026-Q2
Hillsdale Investment Management Inc. trimmed45,900$577K0.1%2026-Q2
Allspring Global Investments Holdings, LLC trimmed44,831$564K0.1%2026-Q2
SEI INVESTMENTS CO added44,637$561K0.1%2026-Q2
Mariner, LLC trimmed41,127$517K0.1%2026-Q2
Caption Management, LLC trimmed37,515$472K0.1%2026-Q2
PRICE T ROWE ASSOCIATES INC /MD/37,076$467K0.1%2026-Q2
MILLENNIUM MANAGEMENT LLC trimmed37,065$466K0.1%2026-Q2
DEUTSCHE BANK AG\ trimmed34,254$431K0.1%2026-Q2
Lighthouse Investment Partners, LLC trimmed34,001$427K0.1%2026-Q2
UBS Group AG trimmed33,602$422K0.1%2026-Q2
BARCLAYS PLC trimmed30,349$381K0.1%2026-Q2
WELLS FARGO & COMPANY/MN added28,163$354K0.1%2026-Q2
Legal & General Group Plc27,533$346K0.1%2026-Q2
Brevan Howard Capital Management LP added27,117$341K0.1%2026-Q2
Dynamic Technology Lab Private Ltd trimmed26,868$338K0.1%2026-Q2
FMR LLC trimmed26,386$332K0.1%2026-Q2
Invesco Ltd. added26,039$327K0.1%2026-Q2
TUDOR INVESTMENT CORP ET AL trimmed25,748$324K0.1%2026-Q2
ALLSTATE CORP new25,287$318K0.1%2026-Q2
AXQ CAPITAL, LP added25,117$316K0.1%2026-Q2
Abel Hall, LLC trimmed24,473$308K0.1%2026-Q2
CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM trimmed24,141$303K0.1%2026-Q2
CITIGROUP INC added24,003$302K0.1%2026-Q2
SUSQUEHANNA INTERNATIONAL GROUP, LLP trimmed23,247$292K0.0%2026-Q2
Corient Private Wealth LP added23,013$289K0.0%2026-Q2
Quantbot Technologies LP trimmed21,568$271K0.0%2026-Q2
MetLife Investment Management, LLC21,402$269K0.0%2026-Q2
JUPITER ASSET MANAGEMENT LTD21,172$266K0.0%2026-Q2
Zurcher Kantonalbank (Zurich Cantonalbank)18,642$234K0.0%2026-Q2
VANGUARD ASSET MANAGEMENT, Ltd17,425$219K0.0%2026-Q2
Graham Capital Management, L.P. added17,179$216K0.0%2026-Q2
MERCER GLOBAL ADVISORS INC /ADV added16,595$209K0.0%2026-Q2
Creative Planning trimmed16,220$204K0.0%2026-Q2
NOMURA HOLDINGS INC trimmed16,058$202K0.0%2026-Q2
IEQ CAPITAL, LLC trimmed15,367$193K0.0%2026-Q2
EP Wealth Advisors, LLC new15,273$192K0.0%2026-Q2
WEALTH ENHANCEMENT ADVISORY SERVICES, LLC trimmed14,811$198K0.0%2026-Q2
MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. trimmed14,208$179K0.0%2026-Q2
Jupiter Topco LLC new13,862$174K0.0%2026-Q2
Cerity Partners LLC trimmed13,617$171K0.0%2026-Q2
LPL Financial LLC added13,300$167K0.0%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.

HoldersTotal shares

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.

Learn how to read institutional ownership