X0303 4 2011-01-24 0001278021 MARKETAXESS HOLDINGS INC MKTX 0001346000 TCV VI L P C/O TECHNOLOGY CROSSOVER VENTURES 528 RAMONA STREET PALO ALTO CA 94301 0 0 1 1 May be part of a 13(d) group 0001370400 Technology Crossover Management VI, L.L.C. C/O TECHNOLOGY CROSSOVER VENTURES 528 RAMONA STREET PALO ALTO CA 94301 0 0 1 1 May be part of a 13(d) group 0001361345 TCV Member Fund, L.P. C/O TECHNOLOGY CROSSOVER VENTURES 528 RAMONA STREET PALO ALTO CA 94301 0 0 1 1 May be part of a 13(d) group 0001343722 Trudeau Robert C/O TECHNOLOGY CROSSOVER VENTURES 528 RAMONA STREET PALO ALTO CA 94301 1 0 1 1 May be part of a 13(d) group 0001082906 HOAG JAY C C/O TECHNOLOGY CROSSOVER VENTURES 528 RAMONA STREET PALO ALTO CA 94301 0 0 1 1 May be part of a 13(d) group 0001197937 KIMBALL RICK C/O TECHNOLOGY CROSSOVER VENTURES 528 RAMONA STREET PALO ALTO CA 94301 0 0 1 1 May be part of a 13(d) group 0001188456 DREW JOHN C/O TECHNOLOGY CROSSOVER VENTURES 528 RAMONA STREET PALO ALTO CA 94301 0 0 1 1 May be part of a 13(d) group 0001188444 REYNOLDS JON Q JR C/O TECHNOLOGY CROSSOVER VENTURES 528 RAMONA STREET PALO ALTO CA 94301 0 0 1 1 May be part of a 13(d) group 0001188458 GRIFFITH WILLIAM C/O TECHNOLOGY CROSSOVER VENTURES 528 RAMONA STREET PALO ALTO CA 94301 0 0 1 1 May be part of a 13(d) group Common Stock 2011-01-24 4 C 0 3472652 A 3472652 I TCV VI, L.P. Common Stock 2011-01-24 4 C 0 27347 A 27347 I TCV Member Fund, L.P. Common Stock 10864 I TCV VI Management, L.L.C. Common Stock 2462 I Robert W. Trudeau Series B Preferred Stock 2011-01-24 4 C 0 34726.52 D Common Stock 3472652 0 I TCV VI, L.P. Series B Preferred Stock 2011-01-24 4 C 0 273.47 D Common Stock 27347 0 I TCV Member Fund, L.P. Each outstanding share of the issuer's Series B Preferred Stock automatically converted into 100 shares of the issuer's Common Stock (plus cash in lieu of any fractional share) pursuant to the terms contained in the issuer's Certificate of Designation of Series B Preferred Stock. These shares are directly held by TCV VI, L.P. Robert W. Trudeau ("Trudeau"), Jay C. Hoag, Richard H. Kimball, John L. Drew, Jon Q. Reynolds, Jr., and William J.G. Griffith IV (collectively, the "TCM VI Members") are Class A Members of Technology Crossover Management VI, L.L.C. ("TCM VI"), which is the sole general partner of TCV VI, L.P. The TCM VI Members and TCM VI may be deemed to beneficially own the shares held by TCV VI, L.P., but the TCM VI Members and TCM VI disclaim beneficial ownership of such shares except to the extent of their pecuniary interest therein. These shares are directly held by TCV Member Fund, L.P. ("TCV MF"). The TCM VI Members are Class A Members of TCM VI, which is a general partner of TCV MF. The TCM VI Members and TCM VI may be deemed to beneficially own certain of the shares held by TCV MF, but the TCM VI Members and TCM VI disclaim beneficial ownership of such shares except to the extent of their pecuniary interest therein. Excludes 2,462 shares directly held of record by Trudeau, which are separately reported on this Form 4. Includes 2,461 shares that were previously reported as held directly by Trudeau, which were transferred from Trudeau to TCV VI Management, L.L.C. ("TCV VI Management") on January 11, 2011, and are now held directly by TCV VI Management. These shares are directly held by TCV VI Management. The TCM VI Members are members of TCV VI Management, but disclaim beneficial ownership of such shares except to the extent of their pecuniary interest therein. Excludes 2,461 shares that were previously held by Trudeau, which were transferred from Trudeau to TCV VI Management on January 11, 2011, and are now reported on this Form 4 as held directly by TCV VI Management. These shares are directly held by Trudeau. Trudeau has sole voting and dispositive power over the shares; however, TCV VI Management owns 100% of the pecuniary interest therein. The TCM VI Members are members of TCV VI Management, but disclaim beneficial ownership of such shares except to the extent of their pecuniary interest therein. Immediately. Not applicable. Frederic D. Fenton Authorized signatory for TCV VI, L.P. 2011-01-26 Frederic D. Fenton Authorized signatory for Technology Crossover Management VI, L.L.C. 2011-01-26 Frederic D. Fenton Authorized signatory for TCV Member Fund, L.P. 2011-01-26 Frederic D. Fenton Authorized signatory for Robert W. Trudeau 2011-01-26 Frederic D. Fenton Authorized signatory for Jay C. Hoag 2011-01-26 Frederic D. Fenton Authorized signatory for Richard H. Kimball 2011-01-26 Frederic D. Fenton Authorized signatory for John L. Drew 2011-01-26 Frederic D. Fenton Authorized signatory for Jon Q. Reynolds Jr. 2011-01-26 Frederic D. Fenton Authorized signatory for William J.G. Griffith IV 2011-01-26