MAX in the 13F filings
Mediaalpha Inc · CUSIP 58450V104
- Quarter end
- 31 Dec 2025
- the date the book describes
- Filed
- 19 Feb 2026
- latest of these filings; the earliest 10 Feb 2026
- Managers listing it
- 26
- at least, of 95 tracked, among listed positions
- Comparable managers
- 92
- filed both Q3 2025 and Q4 2025; 1 listed it in both
- Shares listed
- 6,670,266
- combined, among listed positions
- Reported value
- $86m
- combined, at the quarter end
Among the 92 comparable managers: 20 buyers (opened or added shares) and 7 sellers (trimmed or exited), at least, among listed positions. Their net change in shares was +897,877.
Managers listing MAX in Q4 2025
26 of 26 holders
Largest increases and reductions, by shares
Increases
- Arrowstreet Capital LPexisting position · 855,904 shares now+335,452
- Acadian Asset Management LLCexisting position · 606,171 shares now+186,332
- Balyasny Asset Management LLCnew position · 184,159 shares now+184,159
- Jane Street Group LLCexisting position · 360,129 shares now+183,824
- Citadel Advisors LLCnew position · 169,647 shares now+169,647
Reductions
- Millennium Management LLCexisting position · 751,745 shares now-677,811
- Janus Henderson Group Ltdexisting position · 265,906 shares now-120,249
- D. E. Shaw & Co.existing position · 397,380 shares now-57,503
- AllianceBernstein LPexisting position · 33,930 shares now-4,700
- Verition Fund Management LLCexisting position · 39,303 shares now-1,950
New positions and exits
New (7)
Exited (2)
- Quantbot Technologies LPwas $439k
- Brevan Howard Capital Management LPwas $140k
Ownership over time
Tracked managers listing it, at least.
| Quarter | Holders | Reported value | Buyers | Sellers |
|---|---|---|---|---|
| Q3 2021 | 1 | $4.4m | n.a. | n.a. |
| Q3 2024 | 1 | $1.2m | 1 | 0 |
| Q1 2025 | 1 | $1.2m | 1 | 0 |
| Q2 2025 | 1 | $1.8m | 1 | 0 |
| Q3 2025 | 1 | $1.9m | 0 | 0 |
| Q4 2025 | 1 | $2.1m | 20 | 7 |
| Q1 2026 | 1 | $837k | 12 | 15 |
| Q2 2026 | 1 | $1.1m | 12 | 10 |
Compare with…
Holders over time, buyers and sellers, and the managers holding both, side by side for up to four stocks.
MAX and V →MAX and MA →MAX and MCO →Choose a stock to compare with MAX →
How much of the picture this is
A 13F is a manager’s long US-listed equity book at a quarter end, filed up to 45 days later. It shows no shorts, cash, bonds or performance, and it is never today’s portfolio. Large books are listed to their largest positions, so a manager missing from this table may still hold a small position below that line. These are 95 tracked managers, not the institutional market.
Which funds own MAX, latest filings →Back to the 13F Explorer →