Security key
58450V104
MediaAlpha, Inc. - Class A Common Stock, $0.01 par value per share (MAX)
CUSIP: 58450V104
Q3 2025 13F Holders as of 30 Sep 2025
- Security type / class
- Equity / Class A Common Stock, $0.01 par value per share
- Total 13F shares
- 47,834,261
- Total 13F value
- $544,284,591
- Share change
- -535,399
- Put/Call ratio
- 34%
- SEC-reported price per share
- $11.38
- Number of holders
- 155
- Value change
- -$5,576,109
- Number of buys
- 89
- Number of sells
- 68
- Shares outstanding
- 53,948,069
Holder snapshot
7 signals
Open additional details 1 more signal available
Security identity
Names, identifiers, and filing context for this profile.
1 source field
Report period
Q3 2025
Institutions
155
Top holders
10
MAX full security history
Ownership snapshot
Full 13F holder table
Newer quarter: Q2 2026
MediaAlpha, Inc. SEC filings
MediaAlpha, Inc. company facts
Broader feeds
Reporting periods
Holder history for CUSIP 58450V104
Recent filing periods:
Ownership snapshot
Top reported holders of MAX - MediaAlpha, Inc. - Class A Common Stock, $0.01 par value per share (13F + 13D/G + 3/4/5)
Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.
Comparable stake leader
Eugene Nonko
Disclosed value leader
WHITE MOUNTAINS INSURANCE...
Comparable rows
15/15
Latest evidence
30 Jun 2025
13D/G
13F
3/4/5
Lead comparable stake: 11%
13D/G row: Eugene Nonko
Showing 1-6 of 15 holder rows.
Quick read
Eugene Nonko leads the comparable SEC ownership view at 11%.
15 of 15 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.
Open SEC evidence
Opens Eugene Nonko's linked filing trail.
Comparable ownership
Top 5
Eugene Nonko
11%
VANGUARD GROUP INC
4.6%
BlackRock, Inc.
4.2%
Lara Sweet
0.18%
WHITE MOUNTAINS INSURANCE GROUP LTD
33%
Ownership % is shown only when SEC disclosures are safely comparable across share classes.
Detailed SEC evidence table Showing 1-6 of 15 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| Eugene Nonko |
13D/G
|
11%
|
$50,433,626
5,996,864 shares
|
$0 | 26 Feb 2025 |
| VANGUARD GROUP INC |
13F
13D/G
Company · The Vanguard Group
|
4.6%
from 13D/G
|
$31,308,228
2,859,199 shares
|
— | 30 Jun 2025 |
| BlackRock, Inc. |
13F
13D/G
Company
|
4.2%
from 13D/G
|
$43,837,437
4,003,419 shares
|
— | 30 Jun 2025 |
| Lara Sweet |
3/4/5
Director
|
0.18%
|
$829,705
98,657 shares
|
— | 14 May 2025 |
| WHITE MOUNTAINS INSURANCE GROUP LTD |
3/4/5
13F
10%+ Owner · Company
|
33%
from 13F
|
$339,275,666
17,856,614 shares
|
— | 07 May 2024 |
| Broad Bay Capital Management, LP |
13F
Company
|
4.6%
|
$27,358,652
2,498,507 shares
|
— | 30 Jun 2025 |
How to read this table
Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.
13F holder rows
Institutional holders as of Q3 2025
Investor-level positions for this CUSIP, loaded as an interactive table.
Institutions
155
Shares
47,834,261
Rows available
155
| Investor | Option | Weight % | Change % | SEC-reported value | * Price | Shares | Share Change | Activity | Report Period |
|---|
* SEC-reported price is the security price as of the portfolio date and can indicate the last known price at which the security was still held. The marker flags a reported price that did not pass the local price check.
Compare Q3 2025 vs Q2 2025 Across Filers
Q2 2025 holders
150
Q3 2025 holders
155
Holder diff
5
| Investor | Q2 2025 Shares | Q3 2025 Shares | Share Diff | Share Chg % | Q2 2025 value | Q3 2025 value | Value change | Value Chg % |
|---|
Trend: ostatnie 8 kwartałów (+ wybrane okresy porównania).
Quarterly Holders Trend
Quarterly Value Trend
Quarterly Shares Trend