MediaAlpha, Inc.
MediaAlpha, Inc. (MAX) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · MAX · as of Sep 30, 2025
Ownership Breakdown
163
Institutional Holders
▲ 10 vs Q2
$544.79M
Total Inst. Value
▲ $16.31M vs Q2
54.06M
Shares Outstanding
freeFloat 52.91%
47.88M
13F Shares Held
▼ 389,650 vs Q2
Institutional ownership = 13F shares ÷ total outstanding. Insider % = 100 − free float. Public % = free float − institution %. Data: FMP /symbol-positions-summary + /shares-float + SEC EDGAR.
Top Institutional Holders
MAX largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
WHITE MOUNTAINS INSURANCE GROUP LTD insurance carriers, nec | 17.86M | 31.81% | 31.81% | $203.21B | Nov 13, 2025 | — held |
BLACKROCK, INC. insurance carriers, nec | 3.57M | 6.36% | 6.36% | $40.66B | Nov 12, 2025 | ▼ 430.2K |
VANGUARD GROUP INC insurance carriers, nec | 2.60M | 4.63% | 4.63% | $29.60B | Nov 7, 2025 | ▼ 258.6K |
BROAD BAY CAPITAL MANAGEMENT, LP insurance carriers, nec | 1.47M | 2.62% | 2.62% | $16.71B | Nov 14, 2025 | ▼ 1.03M |
MILLENNIUM MANAGEMENT LLC insurance carriers, nec | 1.43M | 2.55% | 2.55% | $16.27B | Nov 14, 2025 | ▲ 1.25M |
CLEARLINE CAPITAL LP insurance carriers, nec | 1.29M | 2.30% | 2.30% | $14.69B | Nov 14, 2025 | ▼ 134.5K |
GOLDMAN SACHS GROUP INC insurance carriers, nec | 1.28M | 2.28% | 2.28% | $14.57B | Nov 14, 2025 | ▼ 727.2K |
JPMORGAN CHASE & CO insurance carriers, nec | 1.06M | 1.89% | 1.89% | $12.05B | Nov 26, 2025 | ▲ 516.2K |
RENAISSANCE TECHNOLOGIES LLC insurance carriers, nec | 945.1K | 1.68% | 1.68% | $10.76B | Nov 13, 2025 | ▲ 172.8K |
MORGAN STANLEY insurance carriers, nec | 872.0K | 1.55% | 1.55% | $9.92B | May 27, 2026 | ▲ 116.1K |
Data from SEC Form 13F filings. Ownership bar normalised to largest holder. Change flags: isNew / isSoldOut / changeInSharesNumber (FMP extract-analytics/holder).
Institutional Activity
Q3 2025 vs prior quarter
Q3 2025
26
Increased
+4.68M shares1
New Positions
first time holders18
Decreased
−4.47M shares0
Sold Out
fully exitedNet shares change (top 50)
+207.4K
+4.68M / −4.47M
Net new holders
+9
1 new / 0 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
MAX insider trading · insider activity
Source: SEC Form 4
Insiders have been primarily selling shares recently. Selling may be driven by pre-scheduled Rule 10b5-1 plans rather than negative sentiment.
9
Buy transactions
44
Sell transactions
0.20
Buy/Sell ratio
$0M
Total disposed
Recent Insider Transactions
Showing 10 most recent · Common Stock only
| Name · Role | Date | Type | Shares | Price | Value | After Trans. | Filing |
|---|---|---|---|---|---|---|---|
Yeh Kuanling Amy Chief Technology Officer | Jun 5, 2026 | Sale | 3,000 | $8.89 | $26.7K | 570.0K | Form 4 ↗ |
StClair Lauren director | May 15, 2026 | Award | 20,900 | — | — | 20.9K | Form 4 ↗ |
Cramer Keith Chief Revenue Officer | May 15, 2026 | Sale | 13,000 | $8.05 | $104.7K | 293.5K | Form 4 ↗ |
Thompson Patrick Ryan See Remarks | May 15, 2026 | Tax Withhold | 3,253 | $8.05 | $26.2K | 1.12M | Form 4 ↗ |
Thompson Patrick Ryan See Remarks | May 15, 2026 | Tax Withhold | 2,702 | $8.05 | $21.8K | 1.12M | Form 4 ↗ |
Thompson Patrick Ryan See Remarks | May 15, 2026 | Tax Withhold | 8,087 | $8.05 | $65.1K | 1.11M | Form 4 ↗ |
Thompson Patrick Ryan See Remarks | May 15, 2026 | Tax Withhold | 6,252 | $8.05 | $50.3K | 1.10M | Form 4 ↗ |
Yeh Kuanling Amy Chief Technology Officer | May 15, 2026 | Sale | 12,000 | $8.05 | $96.6K | 573.0K | Form 4 ↗ |
COYNE JEFFREY B GENERAL COUNSEL AND SECRETARY | May 15, 2026 | Tax Withhold | 1,808 | $8.05 | $14.6K | 604.2K | Form 4 ↗ |
COYNE JEFFREY B GENERAL COUNSEL AND SECRETARY | May 15, 2026 | Tax Withhold | 1,573 | $8.05 | $12.7K | 602.6K | Form 4 ↗ |
Source: /insider-trading/search (FMP stable). Buy/Sell direction: acquisitionOrDisposition A=Buy, D=Sell. RSU vesting (M-Exempt) excluded from sentiment bar. All data from SEC EDGAR public filings.
About institutional & insider ownership
MediaAlpha, Inc. (MAX) is primarily owned by institutional investors, who hold approximately 88.6% of total shares outstanding. Company insiders own approximately 47.09%, while retail and public investors account for the remaining 0.00%.
The largest institutional shareholder of MediaAlpha, Inc. is WHITE MOUNTAINS INSURANCE GROUP LTD, holding approximately 17.86 million shares — equal to 31.81% of outstanding shares — as of September 30, 2025.
A total of 163 institutional investors currently hold MAX stock, with a combined institutional value of approximately $544,791,719 as of the most recent 13F filing period.
Frequently asked questions
MAX ownershipMediaAlpha, Inc. (MAX) is primarily owned by institutional investors, who hold approximately 88.6% of shares. The largest shareholder is WHITE MOUNTAINS INSURANCE GROUP LTD with a 31.81% stake. Company insiders hold 47.09%. Data sourced from SEC Form 13F as of September 30, 2025.