MarketAxess Holdings
MKTX
509 hedge funds and large institutions have $8.05B invested in MarketAxess Holdings in 2025 Q1 according to their latest regulatory filings, with 79 funds opening new positions, 200 increasing their positions, 181 reducing their positions, and 83 closing their positions.
113% more call options, than puts
Call options by funds: $40.6M | Put options by funds: $19.1M
100% more funds holding in top 10
Funds holding in top 10: 2 → 4 (+2)
10% more repeat investments, than reductions
Existing positions increased: 200 | Existing positions reduced: 181
5% less first-time investments, than exits
New positions opened: 79 | Existing positions closed: 83
1.19% less ownership
Funds ownership: 99.95% → 98.76% (-1.2%)
2% less funds holding
Funds holding: 518 → 509 (-9)
5% less capital invested
Capital invested by funds: $8.52B → $8.05B (-$463M)
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
Millennium Management
New York
|
+$99.7M |
| 2 |
Citadel Advisors
Miami,
Florida
|
+$78.5M |
| 3 |
Holocene Advisors
New York
|
+$52.6M |
| 4 |
American Century Companies
Kansas City,
Missouri
|
+$42.5M |
| 5 |
BAM
Burgundy Asset Management
Toronto,
Ontario, Canada
|
+$33.2M |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
BlackRock
New York
|
-$117M |
| 2 |
Artisan Partners
Milwaukee,
Wisconsin
|
-$55.7M |
| 3 |
GAM
GuardCap Asset Management
London,
United Kingdom
|
-$50.5M |
| 4 |
JP Morgan Chase
New York
|
-$38.9M |
| 5 |
State Street
Boston,
Massachusetts
|
-$34.5M |
MKTX Hedge Fund Activity: Q1 2025 in Review
509 of the 7,457 institutional investors tracked by Wall St. Rank reported a position in MarketAxess Holdings (MKTX) for Q1 2025, worth a combined $8.05B — down 5.4% from $8.52B a quarter earlier.
Sellers outnumbered buyers: 83 funds closed out of MKTX and 79 opened new positions — a net loss of 4 holders — while 181 trimmed existing stakes and 200 added.
The largest buyer was Millennium Management, adding an estimated $99.7M. The largest seller was BlackRock, cutting an estimated $117M.
- 509 institutional investors held MarketAxess Holdings (MKTX) as of Q1 2025, down from 518 in Q4 2024.
- Funds reported $8.05B of MarketAxess Holdings stock for Q1 2025, down 5.4% quarter-over-quarter.
- 79 funds opened new MarketAxess Holdings positions in Q1 2025 and 83 closed out, a net change of -4 holders.
- The largest MarketAxess Holdings buyer in Q1 2025 was Millennium Management, an estimated $99.7M added.
- The largest MarketAxess Holdings seller in Q1 2025 was BlackRock, an estimated $117M sold.
Based on aggregated 13F filings for Q1 2025.