MarketAxess Holdings Inc. (MKTX) Ownership
MKTX ownership summary
as of October 18, 2026- Institutions
- 114.6% of shares outstanding
- Insiders
- 0.74% of shares outstanding
- Shares outstanding
- 35.2M
- Float
- 29.6M shares available to trade
- Short interest
- 11.81% 3.2M shares short
- Days to cover
- 3.46 short interest up 36.6% vs prior month
- Institutions 114.62%
- Insiders 0.74%
MKTX top institutional holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | BlackRock Inc | 11.36% | 4.0M | $658.5M | −75,318 (−1.8%) | June 30, 2026 |
| 2 | PRIMECAP Management Company | 9.96% | 3.5M | $577.0M | +157,780 (+4.7%) | June 30, 2026 |
| 3 | North Reef Capital Management LP | 9.65% | 3.4M | $559.0M | +1.5M (+81.1%) | June 30, 2026 |
| 4 | Vanguard Portfolio Management, LLC | 5.97% | 2.1M | $345.8M | −63,398 (−2.9%) | June 30, 2026 |
| 5 | AQR Capital Management LLC | 5.65% | 2.0M | $327.2M | −696,457 (−26.0%) | June 30, 2026 |
| 6 | Vanguard Capital Management, LLC | 4.39% | 1.5M | $254.6M | −62,589 (−3.9%) | June 30, 2026 |
| 7 | FMR Inc | 3.99% | 1.4M | $231.3M | −114,423 (−7.5%) | June 30, 2026 |
| 8 | State Street Corp | 3.64% | 1.3M | $211.0M | +912 (+0.1%) | June 30, 2026 |
| 9 | Neuberger Berman Group LLC | 3.49% | 1.2M | $202.5M | +263,900 (+27.3%) | June 30, 2026 |
| 10 | The Goldman Sachs Group Inc | 2.93% | 1.0M | $169.8M | +522,266 (+102.6%) | June 30, 2026 |
| 11 | Bank of Montreal | 2.89% | 1.0M | $167.4M | −3,535 (−0.3%) | June 30, 2026 |
| 12 | BMO Capital Markets Corp. | 2.89% | 1.0M | $167.4M | −3,535 (−0.3%) | June 30, 2026 |
| 13 | Geode Capital Management, LLC | 2.83% | 995K | $163.8M | +131,785 (+15.3%) | June 30, 2026 |
| 14 | Van Eck Associates Corporation | 2.63% | 925K | $152.2M | −314,668 (−25.4%) | June 30, 2026 |
| 15 | Dimensional Fund Advisors, Inc. | 1.70% | 598K | $98.4M | +16,410 (+2.8%) | June 30, 2026 |
| 16 | NORGES BANK | 1.63% | 572K | $94.2M | +68,567 (+13.6%) | June 30, 2026 |
| 17 | Two Sigma Investments LLC | 1.55% | 544K | $89.5M | +19,866 (+3.8%) | June 30, 2026 |
| 18 | GuardCap Asset Management Limited | 1.52% | 536K | $88.3M | −107,046 (−16.6%) | June 30, 2026 |
| 19 | Azora Capital LP | 1.46% | 513K | $84.5M | +513,081 (0.0%) | June 30, 2026 |
| 20 | Davis Asset Management, L.P. | 1.42% | 500K | $82.3M | +391,154 (+359.4%) | June 30, 2026 |
Value at the latest close. Change = shares bought or sold in the latest quarterly filing (13F). In the top 20, 11 holders added 3.6M shares and 9 cut 1.4M.
MKTX top mutual fund and ETF holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | iShares Core S&P Small-Cap ETF | 5.99% | 2.1M | $346.9M | — | September 30, 2026 |
| 2 | Vanguard Capital Opportunity Inv | 5.21% | 1.8M | $301.8M | — | June 30, 2026 |
| 3 | Vanguard MStar Total Stk Mkt Idx Invest | 3.05% | 1.1M | $176.9M | −1,222 (−0.1%) | August 31, 2026 |
| 4 | PRIMECAP Odyssey Aggressive Growth | 2.66% | 938K | $154.4M | +42,960 (+4.8%) | June 30, 2026 |
| 5 | Vanguard Small Cap Index | 2.25% | 792K | $130.3M | +14,645 (+1.9%) | September 30, 2026 |
| 6 | BlackRock Event Driven Equity Instl | 1.49% | 525K | $86.4M | +262,515 (+100.0%) | August 31, 2026 |
| 7 | GuardCap Global Equity I USD Acc | 1.13% | 398K | $65.5M | −30,580 (−7.1%) | April 30, 2026 |
| 8 | PRIMECAP Odyssey Growth | 1.12% | 395K | $65.1M | +50,590 (+14.7%) | June 30, 2026 |
| 9 | State Street SPDR Port S&P 600 Sm CpETF | 0.91% | 320K | $52.7M | — | September 30, 2026 |
| 10 | AQR Long-Short Equity I | 0.77% | 272K | $44.7M | +100,526 (+58.7%) | June 30, 2026 |
| 11 | Vanguard MStar Small Cap Value Index | 0.73% | 258K | $42.4M | +11,112 (+4.5%) | September 30, 2026 |
| 12 | Vanguard Tax-Managed Small Cap Adm | 0.67% | 236K | $38.9M | — | September 30, 2026 |
| 13 | Vanguard MStar Small Cap Growth Indx Inv | 0.63% | 221K | $36.3M | −2,613 (−1.2%) | September 30, 2026 |
| 14 | GS Glb Sm Cp CORE Eq Base Inc USD Snap | 0.60% | 211K | $34.7M | +26,933 (+14.6%) | July 31, 2026 |
| 15 | Vanguard Dividend Appreciation ETF | 0.57% | 199K | $32.8M | −2,067 (−1.0%) | September 30, 2026 |
| 16 | Schwab US Small-Cap ETF™ | 0.53% | 185K | $30.5M | +117 (+0.1%) | September 30, 2026 |
| 17 | BNP Paribas US Small Cap ClassicC | 0.51% | 181K | $29.7M | −346 (−0.2%) | August 31, 2026 |
| 18 | iShares S&P Small-Cap 600 Growth ETF | 0.50% | 177K | $29.1M | — | September 30, 2026 |
| 19 | Fidelity Extended Market Index | 0.50% | 175K | $28.8M | −2,111 (−1.2%) | August 31, 2026 |
| 20 | First Trust Financials AlphaDEX® ETF | 0.44% | 153K | $25.2M | — | September 30, 2026 |
Funds report holdings monthly or quarterly; dates differ by fund.
MKTX insider transactions
latest 4| Date | Name | Transaction | Price | Shares | Value |
|---|---|---|---|---|---|
| 2026-04-10 | Scott Pintoff | Sell | $171.96 | 100 | $17,196 |
| 2026-01-12 | Scott Pintoff | Sell | $168.63 | 100 | $16,863 |
| 2025-09-12 | Kevin M Mcpherson | Sell | $185.32 | 1,494 | $276,868 |
| 2025-09-08 | Stephen P Casper | Sell | $186.59 | 1,600 | $298,544 |
Reported trades by company officers, directors and other filers (including disclosures by members of Congress where EODHD lists them). "—" where the filing gives no share count.
MKTX shares outstanding
Year-end shares outstanding, adjusted for splits.
Who owns MKTX
Institutional investors own 114.6% of MarketAxess's shares and insiders 0.74%. The largest holder is BlackRock Inc with 11.36% of the shares (4.0M), as of June 30, 2026. Among the top 20 institutions, 11 added shares and 9 reduced their stake in the latest filings. Short interest is 11.81% of the float, or 3.46 days of average trading volume. The share count fell 2.4% since 2014.
Related: MKTX analyst forecast, MKTX key metrics, MKTX dividend history. See the MKTX stock overview for the latest quote and news.
MKTX ownership FAQ
Who owns the most MarketAxess stock?
The largest shareholders of MarketAxess are BlackRock Inc (11.36%), PRIMECAP Management Company (9.96%), North Reef Capital Management LP (9.65%), Vanguard Portfolio Management, LLC (5.97%), AQR Capital Management LLC (5.65%).
What percentage of MarketAxess is owned by institutions?
Institutions hold 114.6% of MarketAxess's shares outstanding; insiders hold 0.74%.
Which funds own MarketAxess?
The largest fund holders of MarketAxess are iShares Core S&P Small-Cap ETF (5.99%), Vanguard Capital Opportunity Inv (5.21%), Vanguard MStar Total Stk Mkt Idx Invest (3.05%), PRIMECAP Odyssey Aggressive Growth (2.66%), Vanguard Small Cap Index (2.25%).
What is MarketAxess's short interest?
3.2M shares of MarketAxess were sold short, 11.81% of the float; at the average daily volume it would take 3.46 days to cover.
Are insiders buying or selling MarketAxess?
Of the latest 4 reported insider transactions in MarketAxess (since September 8, 2025), 0 were purchases and 4 were sales.
How many shares of MarketAxess are outstanding?
MarketAxess has 35.2M shares outstanding, of which 29.6M are in the public float.