MarketAxess Holdings Inc.
MX ˙ BMV ˙ US57060D1081
SecurityMX:MKTX / MarketAxess Holdings Inc.
InstitutionRenaissance Technologies Llc
ManagerJames Simons
Latest Disclosed Ownership167,100 shares
Latest Disclosed Value $ 27,568,158
Renaissance Technologies Llc reports 5.06% decrease in ownership of MKTX / MarketAxess Holdings Inc.

On May 14, 2026 - Renaissance Technologies Llc filed a 13F-HR form disclosing ownership of 167,100 shares of MarketAxess Holdings Inc. (MX:MKTX) valued at $27,568,158 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 176,000 shares of MarketAxess Holdings Inc.. This represents a change in shares of -5.06% during the quarter.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

Upgrade to unlock premium data and export to Excel .

Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-14 2026-03-31 13F MARKETAXESS HLDGS COM 57060D108 167,100 -8,900 -5.06 27,568 -13.58 0.0431
2026-02-12 2025-12-31 13F MARKETAXESS HLDGS COM 57060D108 176,000 -69,000 -28.16 31,900 -25.28 0.0495
2025-11-13 2025-09-30 13F MARKETAXESS HLDGS COM 57060D108 245,000 54,400 28.54 42,691 0.29 0.0564
2025-08-13 2025-06-30 13F MARKETAXESS HLDGS COM 57060D108 190,600 61,100 47.18 42,569 51.94 0.0566
2025-05-14 2025-03-31 13F MARKETAXESS HLDGS COM 57060D108 129,500 -98,380 -43.17 28,017 -45.61 0.0424
2025-02-13 2024-12-31 13F MARKETAXESS HLDGS COM 57060D108 227,880 40,270 21.46 51,510 7.17 0.0763
2024-11-13 2024-09-30 13F MARKETAXESS HLDGS COM 57060D108 187,610 22,974 13.95 48,066 45.59 0.0723
2024-08-09 2024-06-30 13F MARKETAXESS HLDGS COM 57060D108 164,636 159,436 3,066.08 33,014 3,301,300.00 0.0560
2024-05-13 2024-03-31 13F MARKETAXESS HLDGS COM 57060D108 5,200 5,200 1 0.0018
2024-02-13 2023-12-31 13F MARKETAXESS HLDGS COM 57060D108 0 -121,110 -100.00 0 -100.00
2023-11-14 2023-09-30 13F MARKETAXESS HLDGS COM 57060D108 121,110 60,300 99.16 26 66.67 0.0441
2023-08-11 2023-06-30 13F MARKETAXESS HLDGS COM 57060D108 60,810 -3,163 -4.94 16 -40.00 0.0229
2023-05-12 2023-03-31 13F MARKETAXESS HLDGS COM 57060D108 63,973 -3,100 -4.62 25 38.89 0.0332
2023-02-13 2022-12-31 13F MARKETAXESS HLDGS COM 57060D108 67,073 -69,510 -50.89 19 -99.94 0.0256
2022-11-14 2022-09-30 13F MARKETAXESS HLDGS COM 57060D108 136,583 77,110 129.66 30,388 99.58 0.0430
2022-08-12 2022-06-30 13F MARKETAXESS HLDGS COM 57060D108 59,473 33,500 128.98 15,226 72.32 0.0180
2022-05-13 2022-03-31 13F MARKETAXESS HLDGS COM 57060D108 25,973 -65,810 -71.70 8,836 -76.59 0.0104
2022-02-11 2021-12-31 13F MARKETAXESS HLDGS COM 57060D108 91,783 -93,690 -50.51 37,748 -51.62 0.0470
2021-11-12 2021-09-30 13F MARKETAXESS HLDGS COM 57060D108 185,473 -118,670 -39.02 78,027 -44.66 0.1008
2021-08-13 2021-06-30 13F MARKETAXESS HLDGS COM 57060D108 304,143 -148,910 -32.87 140,998 -37.50 0.1760
2021-05-13 2021-03-31 13F MARKETAXESS HLDGS COM 57060D108 453,053 -261,900 -36.63 225,584 -44.70 0.2806
2021-02-10 2020-12-31 13F MARKETAXESS HLDGS COM 57060D108 714,953 -251,711 -26.04 407,924 -12.38 0.4430
2020-11-13 2020-09-30 13F MARKETAXESS HLDGS COM 57060D108 966,664 -68,900 -6.65 465,536 -10.26 0.4648
2020-08-13 2020-06-30 13F MARKETAXESS HLDGS COM 57060D108 1,035,564 -165,800 -13.80 518,735 29.83 0.4478
2020-05-14 2020-03-31 13F MARKETAXESS HLDGS COM 57060D108 1,201,364 245,410 25.67 399,538 10.24 0.3880
2020-02-13 2019-12-31 13F MARKETAXESS HLDGS COM 57060D108 955,954 237,744 33.10 362,412 54.08 0.2785
2019-11-13 2019-09-30 13F MARKETAXESS HLDGS COM 57060D108 718,210 224,210 45.39 235,214 48.14 0.1991
2019-08-12 2019-06-30 13F MARKETAXESS HLDGS COM 57060D108 494,000 2,800 0.57 158,781 31.36 0.1398
2019-05-14 2019-03-31 13F MARKETAXESS HLDGS COM 57060D108 491,200 118,300 31.72 120,874 53.40 0.1099
2019-02-12 2018-12-31 13F MARKETAXESS HLDGS COM 57060D108 372,900 50,890 15.80 78,797 37.10 0.0863
2018-11-13 2018-09-30 13F MARKETAXESS HLDGS COM 57060D108 322,010 12,610 4.08 57,476 -6.11 0.0591
2018-08-13 2018-06-30 13F/A-1 MARKETAXESS HLDGS COM 57060D108 309,400 7,800 2.59 61,218 -6.65 0.0667
2018-08-13 2018-06-30 13F MARKETAXESS HLDGS COM 57060D108 301,600 65,580
2018-05-14 2018-03-31 13F MARKETAXESS HLDGS COM 57060D108 301,600 19,690 6.98 65,580 15.31 0.0717
2018-02-13 2017-12-31 13F MARKETAXESS HLDGS COM 57060D108 281,910 -90,900 -24.38 56,875 -17.32 0.0627
2017-11-13 2017-09-30 13F MARKETAXESS HLDGS COM 57060D108 372,810 91,372 32.47 68,787 21.54 0.0809
2017-08-11 2017-06-30 13F MARKETAXESS HLDGS COM 57060D108 281,438 102,328 57.13 56,597 68.54 0.0722
2017-05-12 2017-03-31 13F MARKETAXESS HLDGS COM 57060D108 179,110 -4,400 -2.40 33,581 24.55 0.0469
2017-02-13 2016-12-31 13F MARKETAXESS HLDGS COM 57060D108 183,510 183,510 26,961 0.0427
2016-11-14 2016-09-30 13F MARKETAXESS HLDGS COM 57060D108 0 -2,500 -100.00 0 -100.00
2016-08-12 2016-06-30 13F MARKETAXESS HLDGS COM 57060D108 2,500 -104,200 -97.66 363 -97.27 0.0007
2016-05-13 2016-03-31 13F MARKETAXESS HLDGS COM 57060D108 106,700 -82,610 -43.64 13,319 -36.95 0.0253
2016-02-11 2015-12-31 13F MARKETAXESS HLDGS COM 57060D108 189,310 -23,100 -10.88 21,125 7.08 0.0460
2015-11-12 2015-09-30 13F MARKETAXESS HLDGS COM 57060D108 212,410 15,210 7.71 19,729 7.84 0.0471
2015-08-14 2015-06-30 13F MARKETAXESS HLDGS COM 57060D108 197,200 24,100 13.92 18,294 27.48 0.0417
2015-05-13 2015-03-31 13F MARKETAXESS HLDGS COM 57060D108 173,100 -6,400 -3.57 14,350 11.48 0.0306
2015-02-13 2014-12-31 13F MARKETAXESS HLDGS COM 57060D108 179,500 -185,610 -50.84 12,872 -43.01 0.0311
2014-11-12 2014-09-30 13F MARKETAXESS HLDGS COM 57060D108 365,110 -223,300 -37.95 22,586 -28.99 0.0618
2014-08-13 2014-06-30 13F MARKETAXESS HLDGS COM 57060D108 588,410 583,010 10,796.48 31,809 8,590.98 0.0742
2014-05-14 2014-03-31 13F MEASUREMENT SPECIALTIES COM 583421102 5,400 -400 -6.90 366 3.98 0.0009
2014-05-14 2014-03-31 13F MARKETAXESS HLDGS COM 57060D108 500,510 81,810 29,640 0.0711
2014-02-14 2013-12-31 13F MEASUREMENT SPECIALTIES COM 583421102 5,800 -408,300 -98.60 352 -98.58 0.0008
2014-02-14 2013-12-31 13F MARKETAXESS HLDGS COM 57060D108 418,700 4,600 28,023 0.0671
2013-11-13 2013-09-30 13F MARKETAXESS HLDGS COM 57060D108 414,100 -85,510 -17.12 24,827 6.29 0.0602
2013-08-12 2013-06-30 13F MARKETAXESS HLDGS COM 57060D108 499,610 499,610 23,357 0.0612
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.