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 163 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	$166.07M 17,856,614 shares	52.99%	0(0.00%)Unchanged	SEC filing ↗ May 12, 2026	▾
02	BlackRock, Inc. CIK 2012383 · View history	$32.33M 3,476,687 shares	0.00%	-74.78K(-2.10%)Reduced	SEC filing ↗ May 13, 2026	▾
03	Clearline Capital LP CIK 1600136 · View history	$24.09M 2,590,670 shares	1.87%	+1.29M(+99.10%)Added	SEC filing ↗ May 15, 2026	▾
04	JPMORGAN CHASE & CO CIK 19617 · Amended · View history	$16.48M 1,745,679 shares	0.00%	+377.78K(+27.60%)Added	SEC filing ↗ May 13, 2026	▾
05	VANGUARD CAPITAL MANAGEMENT LLC CIK 2100119 · Amended · View history	$12.89M 1,385,729 shares	0.00%	—	SEC filing ↗ May 15, 2026	▾
06	J. Goldman & Co LP CIK 1412741 · View history	$11.00M 1,182,673 shares	0.51%	+396.30K(+50.40%)Added	SEC filing ↗ May 15, 2026	▾
07	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$9.95M 1,070,084 shares	0.00%	+292.78K(+37.70%)Added	SEC filing ↗ May 15, 2026	▾
08	ARROWSTREET CAPITAL, LIMITED PARTNERSHIP CIK 1164508 · View history	$9.88M 1,061,981 shares	0.01%	+206.08K(+24.10%)Added	SEC filing ↗ May 14, 2026	▾
09	JACOBS ASSET MANAGEMENT, LLC CIK 1351063 · View history	$8.60M 924,443 shares	5.15%	+219.14K(+31.10%)Added	SEC filing ↗ May 15, 2026	▾
10	ACADIAN ASSET MANAGEMENT LLC CIK 916542 · View history	$7.87M 847,199 shares	0.01%	+241.03K(+39.80%)Added	SEC filing ↗ May 13, 2026	▾
11	STATE STREET CORP CIK 93751 · View history	$7.79M 838,161 shares	0.00%	+106.75K(+14.60%)Added	SEC filing ↗ May 15, 2026	▾
12	Shay Capital LLC CIK 1723643 · View history	$7.21M 775,000 shares	1.02%	+184.00K(+31.10%)Added	SEC filing ↗ May 15, 2026	▾
13	JACOBS LEVY EQUITY MANAGEMENT, INC CIK 884414 · View history	$6.98M 750,054 shares	0.03%	+49.56K(+7.10%)Added	SEC filing ↗ May 15, 2026	▾
14	RENAISSANCE TECHNOLOGIES LLC CIK 1037389 · View history	$6.69M 719,300 shares	0.01%	-326.10K(-31.20%)Reduced	SEC filing ↗ May 14, 2026	▾
15	MORGAN STANLEY CIK 895421 · View history	$6.54M 703,018 shares	0.00%	-257.14K(-26.80%)Reduced	SEC filing ↗ May 15, 2026	▾
16	Nuveen, LLC CIK 1871926 · View history	$6.52M 701,399 shares	0.00%	+34.86K(+5.20%)Added	SEC filing ↗ Apr 30, 2026	▾
17	GOLDMAN SACHS GROUP INC CIK 886982 · View history	$5.80M 623,421 shares	0.00%	-105.95K(-14.50%)Reduced	SEC filing ↗ May 15, 2026	▾
18	DIMENSIONAL FUND ADVISORS LP CIK 354204 · View history	$5.77M 620,669 shares	0.00%	+300.87K(+94.10%)Added	SEC filing ↗ May 7, 2026	▾
19	VANGUARD PORTFOLIO MANAGEMENT LLC CIK 2100121 · Amended · View history	$5.08M 546,745 shares	0.00%	—	SEC filing ↗ May 8, 2026	▾
20	SPEECE THORSON CAPITAL GROUP INC CIK 900169 · View history	$4.64M 499,011 shares	1.06%	+499.01KNew	SEC filing ↗ Apr 29, 2026	▾

Showing 20 / 163 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

163

Cancelled or null records excluded

Disclosed shares

48,491,820

Not deduplicated across managers

Disclosed value

$451.96M

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. · Q1 2026

Explore all 163 reporting institutions.

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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.