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MKTXFinancialsCommon Stock

Marketaxess Holdings Inc

Held by 10 tracked managers as of Q2 2026 · CUSIP ⓘCUSIP: A 9-character ID for one specific security - one share class of one company, or one bond. Tickers can change and can mean different things in different countries; a CUSIP always identifies exactly the same security, which is why filings use it. Guide 57060D108 · Sector ⓘGICS sectors: The 11-sector system most investors know (Global Industry Classification Standard): Technology, Health Care, Financials and so on. This site assigns each company a GICS-style sector from its SIC code, with a few hand corrections, so sector pages match the names investors expect. Guide

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In plain English: 10 of the investors we track own this stock. In the latest quarter, 6 of them bought more of it and 4 sold some or all of theirs. That tells you what they did last quarter — not what the stock will do next.

Educational and informational only, not personalized investment advice. Based on public filings that may be delayed or contain errors; verify with the original filings. Disclaimer

Managers holding
10
-1 vs last quarter (like-for-like)
Total value held
$230.57M
Across tracked managers
Average weight ⓘOn average, how big this stock is in the portfolios that own it (its share of each manager's reported portfolio value).
0.0%
Of each manager's book
QoQ value ⓘLike-for-like: only managers that filed both quarters are compared, so a manager filing late (or confidentially) does not look like buying or selling. Includes price changes.
-$191.22M
-53.6% vs last quarter
Net shares bought
-703.6K
Est. net flow -$81.35M
Quarter activity
6 bought · 4 sold
0 new · 1 sold out

Tracked capital in this stock

Total value held (area) and number of managers (line). Dips can mean a large holder filed that quarter confidentially (e.g. Norges Bank in Q1/Q3).

Chart: Tracked capital in this stock

Aggregate buying and selling

Net share change reported each quarter

Chart: Aggregate buying and selling

Who owns MKTX?

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Who owns MKTX? — Q2 2026

Holders ranked by position size, with each one's quarter-over-quarter change.

CSV Excel
Column filters

Numbers accept 1.5M, 2B, 250K. Percent columns take percent (5 = 5%).

# Manager Fund Shares Value ↓ % of their portfolio QoQ Δ shares Δ shares % Est. Δ value ⓘChange in shares × this quarter's price
1 Norges Bank Norges Bank Investment Management 572.42K $64.96M 0.0% — — — —
2 Two Sigma Two Sigma Investments 543.89K $61.73M 0.0% Added +19.9K +3.8% +$2.25M
3 Ken Griffin Citadel Advisors 481.69K $54.67M 0.0% Added +399.5K +486.3% +$45.34M
4 Jim Simons Renaissance Technologies 200.00K $22.70M 0.0% Added +32.9K +19.7% +$3.73M
5 Israel Englander Millennium Management 109.59K $12.44M 0.0% Reduced -977.6K -89.9% -$110.95M
6 Matthew McLennan First Eagle Investment Management 49.58K $5.63M 0.0% Added +49.6K +225250.0% +$5.62M
7 David Shaw D.E. Shaw & Co. 47.98K $5.44M 0.0% Added +44.7K +1347.7% +$5.07M
8 Fred Alger Fred Alger Management 11.40K $1.29M 0.0% Reduced -196 -1.7% -$22.24K
9 Steve Cohen Point72 Asset Management 8.10K $919.27K 0.0% Reduced -244.7K -96.8% -$27.77M
10 Ray Dalio Bridgewater Associates 7.02K $797.15K 0.0% Added +1.4K +25.2% +$160.70K

Sold out completely this quarter

CSV Excel
Column filters

Numbers accept 1.5M, 2B, 250K. Percent columns take percent (5 = 5%).

Manager Fund Shares sold Value last quarter ↓
Baillie Gifford Baillie Gifford & Co -29.0K $4.79M

Politician trades

Politician trades in MKTX

CSV Excel
Column filters

Numbers accept 1.5M, 2B, 250K. Percent columns take percent (5 = 5%).

No politician trades match these filters.