Company · Ownership research

MediaAlpha, Inc. MAX

CIK 0001818383 · CUSIP 58450V104

Insider trading Initial holdings Institutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP 58450V104 (MAX), not CUSIP 58450V904 (MAX), CUSIP 58450V954 (MAX), and does not merge CUSIPs.

This page lists the top 20 of 153 rows by value; the complete set is available through the API.

Some filings reported values in thousands; those figures were scaled ×1,000 to dollars.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value

#	Manager	Value	Manager weight	Change vs prior	Source
01	WHITE MOUNTAINS INSURANCE GROUP LTD CIK 776867 · View history	$195.53M 17,856,614 shares	100.00%	0(0.00%)Unchanged	SEC filing ↗ Aug 11, 2025	▾
02	BlackRock, Inc. CIK 2012383 · View history	$43.84M 4,003,419 shares	0.00%	+305.69K(+8.30%)Added	SEC filing ↗ Aug 12, 2025	▾
03	VANGUARD GROUP INC CIK 102909 · View history	$31.31M 2,859,199 shares	0.00%	-54.13K(-1.90%)Reduced	SEC filing ↗ Aug 11, 2025	▾
04	Broad Bay Capital Management, LP CIK 1759115 · View history	$27.36M 2,498,507 shares	3.85%	-249.27K(-9.10%)Reduced	SEC filing ↗ Aug 14, 2025	▾
05	GOLDMAN SACHS GROUP INC CIK 886982 · View history	$21.98M 2,007,186 shares	0.00%	+1.27M(+172.50%)Added	SEC filing ↗ Aug 14, 2025	▾
06	Clearline Capital LP CIK 1600136 · View history	$15.61M 1,425,308 shares	1.37%	-1.23M(-46.30%)Reduced	SEC filing ↗ Aug 14, 2025	▾
07	Nuveen, LLC CIK 1871926 · View history	$9.86M 900,790 shares	0.00%	+394.88K(+78.10%)Added	SEC filing ↗ Aug 12, 2025	▾
08	D. E. Shaw & Co., Inc. CIK 1009207 · View history	$9.80M 895,348 shares	0.01%	+224.66K(+33.50%)Added	SEC filing ↗ Aug 14, 2025	▾
09	JACOBS ASSET MANAGEMENT, LLC CIK 1351063 · View history	$8.75M 798,666 shares	4.98%	+390.25K(+95.60%)Added	SEC filing ↗ Aug 13, 2025	▾
10	RENAISSANCE TECHNOLOGIES LLC CIK 1037389 · View history	$8.46M 772,300 shares	0.01%	+206.80K(+36.60%)Added	SEC filing ↗ Aug 13, 2025	▾
11	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$8.37M 764,702 shares	0.00%	+36.95K(+5.10%)Added	SEC filing ↗ Aug 8, 2025	▾
12	MORGAN STANLEY CIK 895421 · View history	$8.28M 755,926 shares	0.00%	+18.00K(+2.40%)Added	SEC filing ↗ Aug 14, 2025	▾
13	Shay Capital LLC CIK 1723643 · View history	$7.34M 670,000 shares	1.67%	+98.16K(+17.20%)Added	SEC filing ↗ Aug 14, 2025	▾
14	STATE STREET CORP CIK 93751 · View history	$7.15M 652,838 shares	0.00%	+29.05K(+4.70%)Added	SEC filing ↗ Aug 14, 2025	▾
15	JANUS HENDERSON GROUP PLC CIK 1274173 · View history	$6.93M 632,888 shares	0.00%	+619.03K(+4,465.60%)Added	SEC filing ↗ Aug 14, 2025	▾
16	AQR CAPITAL MANAGEMENT LLC CIK 1167557 · View history	$6.59M 601,593 shares	0.01%	+43.80K(+7.90%)Added	SEC filing ↗ Aug 14, 2025	▾
17	JPMORGAN CHASE & CO CIK 19617 · View history	$5.94M 542,246 shares	0.00%	+233.95K(+75.90%)Added	SEC filing ↗ Aug 12, 2025	▾
18	ACADIAN ASSET MANAGEMENT LLC CIK 916542 · View history	$5.82M 532,437 shares	0.01%	+211.13K(+65.70%)Added	SEC filing ↗ Aug 7, 2025	▾
19	UBS Group AG CIK 1610520 · View history	$5.79M 528,380 shares	0.00%	+23.53K(+4.70%)Added	SEC filing ↗ Aug 14, 2025	▾
20	Qube Research & Technologies Ltd CIK 1729829 · View history	$5.76M 526,349 shares	0.01%	+56.72K(+12.10%)Added	SEC filing ↗ Aug 14, 2025	▾

Showing 20 / 153 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

153

Cancelled or null records excluded

Disclosed shares

48,268,486

Not deduplicated across managers

Disclosed value

$528.49M

Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

MediaAlpha, Inc. · Q2 2025

Explore all 153 reporting institutions.

This page includes 20 of 153 reporting institutions. Log in to look up the full history beyond 3 years, use advanced screening & filtering, download CSV, and get the complete set through the Akkru API.

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Sources, coverage & how to read this data

Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.