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Detailed information regarding the number of shares sold at each separate price will be provided upon request by the Commission staff, the Issuer or a security holder of the Issuer."}],"balance_after":35597,"source":{"system":"sec-edgar","filing":"0001209191-20-028474","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1296468/000120919120028474/doc4.xml","form_type":"4"}},{"id":3152487,"issuer":{"id":3821,"kind":"organization","name":"MARKETAXESS HOLDINGS INC","symbol":"MKTX"},"owners":[{"id":129304,"kind":"person","name":"Themelis Nicholas","position":1,"cik":"0001296468","reported_name":"Themelis Nicholas","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Information Officer"}}],"security":"Common Stock, par value $0.003 per share","published_at":"2020-05-12T16:09:15.000Z","date":"2020-05-08","kind":"sale","acquired":false,"shares":438,"price":478.86,"value":209740.68,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person."},{"field":"price","element":"transactionPricePerShare","label":"F4","text":"The transactions were executed in multiple trades at prices ranging from $478.44 to $479.34. The price above reflects the weighted average sales price. Detailed information regarding the number of shares sold at each separate price will be provided upon request by the Commission staff, the Issuer or a security holder of the Issuer."}],"balance_after":35911,"source":{"system":"sec-edgar","filing":"0001209191-20-028474","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1296468/000120919120028474/doc4.xml","form_type":"4"}},{"id":3152486,"issuer":{"id":3821,"kind":"organization","name":"MARKETAXESS HOLDINGS INC","symbol":"MKTX"},"owners":[{"id":129304,"kind":"person","name":"Themelis Nicholas","position":1,"cik":"0001296468","reported_name":"Themelis Nicholas","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Information Officer"}}],"security":"Common Stock, par value $0.003 per share","published_at":"2020-05-12T16:09:15.000Z","date":"2020-05-08","kind":"sale","acquired":false,"shares":988,"price":477.92,"value":472184.96,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person."},{"field":"price","element":"transactionPricePerShare","label":"F3","text":"The transactions were executed in multiple trades at prices ranging from $477.39 to $478.37. The price above reflects the weighted average sales price. Detailed information regarding the number of shares sold at each separate price will be provided upon request by the Commission staff, the Issuer or a security holder of the Issuer."}],"balance_after":36349,"source":{"system":"sec-edgar","filing":"0001209191-20-028474","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1296468/000120919120028474/doc4.xml","form_type":"4"}},{"id":3152485,"issuer":{"id":3821,"kind":"organization","name":"MARKETAXESS HOLDINGS INC","symbol":"MKTX"},"owners":[{"id":129304,"kind":"person","name":"Themelis Nicholas","position":1,"cik":"0001296468","reported_name":"Themelis Nicholas","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Information Officer"}}],"security":"Common Stock, par value $0.003 per share","published_at":"2020-05-12T16:09:15.000Z","date":"2020-05-08","kind":"sale","acquired":false,"shares":855,"price":476.85,"value":407706.75,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The transactions were executed in multiple trades at prices ranging from $476.27 to $477.21. The price above reflects the weighted average sales price. Detailed information regarding the number of shares sold at each separate price will be provided upon request by the Commission staff, the Issuer or a security holder of the Issuer."}],"balance_after":37337,"source":{"system":"sec-edgar","filing":"0001209191-20-028474","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1296468/000120919120028474/doc4.xml","form_type":"4"}}],"next_cursor":"2020-05-12T16:09:15.000000Z,3152485"}