MARKETAXESS HOLDINGS INC (MKTX) Institutional Ownership and Insiders Activity

MARKETAXESS HOLDINGS INC (MKTX) is widely held by institutional investors, with 2 tracked firms reporting positions valued at approximately $33.19M based on SEC Form 13F filings for the quarter ended June 30, 2026.

Renaissance Technologies LLC is the largest disclosed holder, reporting approximately $27.57M in MKTX holdings in its latest filing.

Institutional ownership among tracked investors remains highly concentrated, with Renaissance Technologies LLC representing the majority of disclosed value.

Recent insider activity includes 16 tracked Form 4 transactions over the last three months, reflecting ongoing executive and director trading activity.