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Such shares of Common Stock are subject to lock-up agreements that, subject to certain exceptions, restrict the sale of such shares until November 11, 2025 except with the prior written consent of J.P. Morgan Securities LLC."},{"field":"price","element":"transactionPricePerShare","label":"F4","text":"On September 12, 2025, Derby Investor distributed 397,013 shares of Common Stock and Derby SPV Investor distributed 119,358 shares of Common Stock to one or more of their respective members or partners in connection with certain charitable gifts made by such members or partners or their direct or indirect owners. Such shares of Common Stock are subject to lock-up agreements that, subject to certain exceptions, restrict the sale of such shares until November 11, 2025 except with the prior written consent of J.P. Morgan Securities LLC."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Bain Capital Investors, LLC (\"BCI\") is the manager of Bain Capital Partners XI, L.P. (\"Partners XI\"), which is the general partner of Bain Capital Fund XI, L.P. (\"Fund XI\"). Fund XI is the (i) sole member of BCPE Derby GP, LLC (\"Derby GP\"), which is the general partner of BCPE Derby Investor, LP (\"Derby Investor\") and (ii) sole member of BCPE Derby (DE) SPV, LLC (\"Derby SPV GP\"), which is the general partner of BCPE Derby (DE) SPV, LP (\"Derby SPV Investor\" and, together with BCI, Partners XI, Fund XI, Derby GP, Derby Investor and Derby SPV GP, the \"Bain Capital Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"(Continued from footnote 1) As a result, the Bain Capital Entities may be deemed to share voting and dispositive power with respect to the shares of the Issuer's common stock, par value $0.01 per share (the \"Common Stock\"), held by Derby Investor and Derby SPV Investor. The Bain Capital Entities disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein."}],"balance_after":13243539,"source":{"system":"sec-edgar","filing":"0001193125-25-205034","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1040508/000119312525205034/ownership.xml","form_type":"4"}},{"id":1040000,"issuer":{"id":1420,"kind":"organization","name":"Waystar Holding Corp.","symbol":"WAY"},"owners":[{"id":52008,"kind":"organization","name":"Bain Capital Investors LLC","position":1,"cik":"0001040508","reported_name":"BAIN CAPITAL INVESTORS LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75354,"kind":"organization","name":"BCPE Derby Investor, LP","position":2,"cik":"0002025342","reported_name":"BCPE Derby Investor, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75355,"kind":"organization","name":"BCPE Derby GP, LLC","position":3,"cik":"0002025234","reported_name":"BCPE Derby GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75356,"kind":"organization","name":"Bain Capital Fund XI, L.P.","position":4,"cik":"0001568889","reported_name":"Bain Capital Fund XI, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75357,"kind":"organization","name":"Bain Capital Partners XI, L.P.","position":5,"cik":"0001851748","reported_name":"Bain Capital Partners XI, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75358,"kind":"organization","name":"BCPE Derby (DE) SPV, LP","position":6,"cik":"0002048434","reported_name":"BCPE Derby (DE) SPV, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75359,"kind":"organization","name":"BCPE Derby (DE) SPV (GP), LLC","position":7,"cik":"0002048242","reported_name":"BCPE Derby (DE) SPV (GP), LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock, par value $0.01 per share","published_at":"2025-09-16T20:30:08.000Z","date":"2025-09-12","kind":"sale","planned":false,"acquired":false,"shares":4295139,"price":39.21,"value":168412400.19,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F3","text":"Pursuant to a registered public offering that closed on September 12, 2025, 298,303 shares of Common Stock were sold by Derby Investor and 3,996,836 shares of Common Stock were sold by Derby SPV Investor at a price of $39.21 (net of underwriting discount)."},{"field":"price","element":"transactionPricePerShare","label":"F3","text":"Pursuant to a registered public offering that closed on September 12, 2025, 298,303 shares of Common Stock were sold by Derby Investor and 3,996,836 shares of Common Stock were sold by Derby SPV Investor at a price of $39.21 (net of underwriting discount)."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Bain Capital Investors, LLC (\"BCI\") is the manager of Bain Capital Partners XI, L.P. (\"Partners XI\"), which is the general partner of Bain Capital Fund XI, L.P. (\"Fund XI\"). Fund XI is the (i) sole member of BCPE Derby GP, LLC (\"Derby GP\"), which is the general partner of BCPE Derby Investor, LP (\"Derby Investor\") and (ii) sole member of BCPE Derby (DE) SPV, LLC (\"Derby SPV GP\"), which is the general partner of BCPE Derby (DE) SPV, LP (\"Derby SPV Investor\" and, together with BCI, Partners XI, Fund XI, Derby GP, Derby Investor and Derby SPV GP, the \"Bain Capital Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"(Continued from footnote 1) As a result, the Bain Capital Entities may be deemed to share voting and dispositive power with respect to the shares of the Issuer's common stock, par value $0.01 per share (the \"Common Stock\"), held by Derby Investor and Derby SPV Investor. The Bain Capital Entities disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein."}],"balance_after":13759910,"source":{"system":"sec-edgar","filing":"0001193125-25-205034","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1040508/000119312525205034/ownership.xml","form_type":"4"}},{"id":1141604,"issuer":{"id":1420,"kind":"organization","name":"Waystar Holding Corp.","symbol":"WAY"},"owners":[{"id":52008,"kind":"organization","name":"Bain Capital Investors LLC","position":1,"cik":"0001040508","reported_name":"BAIN CAPITAL INVESTORS LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75354,"kind":"organization","name":"BCPE Derby Investor, LP","position":2,"cik":"0002025342","reported_name":"BCPE Derby Investor, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75355,"kind":"organization","name":"BCPE Derby GP, LLC","position":3,"cik":"0002025234","reported_name":"BCPE Derby GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75356,"kind":"organization","name":"Bain Capital Fund XI, L.P.","position":4,"cik":"0001568889","reported_name":"Bain Capital Fund XI, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75357,"kind":"organization","name":"Bain Capital Partners XI, L.P.","position":5,"cik":"0001851748","reported_name":"Bain Capital Partners XI, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75358,"kind":"organization","name":"BCPE Derby (DE) SPV, LP","position":6,"cik":"0002048434","reported_name":"BCPE Derby (DE) SPV, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75359,"kind":"organization","name":"BCPE Derby (DE) SPV (GP), LLC","position":7,"cik":"0002048242","reported_name":"BCPE Derby (DE) SPV (GP), LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock, par value $0.01 per share","published_at":"2025-05-21T00:55:01.000Z","date":"2025-05-20","kind":"sale","planned":false,"acquired":false,"shares":451837,"price":37.39,"value":16894185.43,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F5","text":"In connection with the exercise of the underwriters' option to purchase additional shares of Common Stock in a registered public offering that closed on May 20, 2025, 65,295 shares of Common Stock were sold by Derby Investor and 386,542 shares of Common Stock were sold by Derby SPV Investor at a price of $37.3937 (net of underwriting discount)."},{"field":"price","element":"transactionPricePerShare","label":"F5","text":"In connection with the exercise of the underwriters' option to purchase additional shares of Common Stock in a registered public offering that closed on May 20, 2025, 65,295 shares of Common Stock were sold by Derby Investor and 386,542 shares of Common Stock were sold by Derby SPV Investor at a price of $37.3937 (net of underwriting discount)."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Bain Capital Investors, LLC (\"BCI\") is the manager of Bain Capital Partners XI, L.P. (\"Partners XI\"), which is the general partner of Bain Capital Fund XI, L.P. (\"Fund XI\"). Fund XI is the (i) sole member of BCPE Derby GP, LLC (\"Derby GP\"), which is the general partner of BCPE Derby Investor, LP (\"Derby Investor\") and (ii) sole member of BCPE Derby (DE) SPV, LLC (\"Derby SPV GP\"), which is the general partner of BCPE Derby (DE) SPV, LP (\"Derby SPV Investor\" and, together with BCI, Partners XI, Fund XI, Derby GP, Derby Investor and Derby SPV GP, the \"Bain Capital Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"(Continued from footnote 1) As a result, the Bain Capital Entities may be deemed to share voting and dispositive power with respect to the shares of the Issuer's common stock, par value $0.01 per share (the \"Common Stock\"), held by Derby Investor and Derby SPV Investor. The Bain Capital Entities disclaim beneficial ownership of such securities, except to the extent of their pecuniary interest therein."}],"balance_after":18055049,"source":{"system":"sec-edgar","filing":"0000950170-25-075513","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1040508/000095017025075513/ownership.xml","form_type":"4"}},{"id":1141603,"issuer":{"id":1420,"kind":"organization","name":"Waystar Holding Corp.","symbol":"WAY"},"owners":[{"id":52008,"kind":"organization","name":"Bain Capital Investors LLC","position":1,"cik":"0001040508","reported_name":"BAIN CAPITAL INVESTORS LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75354,"kind":"organization","name":"BCPE Derby Investor, LP","position":2,"cik":"0002025342","reported_name":"BCPE Derby Investor, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75355,"kind":"organization","name":"BCPE Derby GP, LLC","position":3,"cik":"0002025234","reported_name":"BCPE Derby GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75356,"kind":"organization","name":"Bain Capital Fund XI, L.P.","position":4,"cik":"0001568889","reported_name":"Bain Capital Fund XI, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75357,"kind":"organization","name":"Bain Capital Partners XI, L.P.","position":5,"cik":"0001851748","reported_name":"Bain Capital Partners XI, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75358,"kind":"organization","name":"BCPE Derby (DE) SPV, LP","position":6,"cik":"0002048434","reported_name":"BCPE Derby (DE) SPV, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75359,"kind":"organization","name":"BCPE Derby (DE) SPV (GP), LLC","position":7,"cik":"0002048242","reported_name":"BCPE Derby (DE) SPV (GP), LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock, par value $0.01 per share","published_at":"2025-05-21T00:55:01.000Z","date":"2025-05-16","kind":"other","planned":false,"acquired":false,"shares":235397,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F4","text":"On May 16, 2025, Derby Investor distributed 235,397 shares of Common Stock to one or more of its members or partners in connection with certain charitable gifts made by such members or partners or their direct or indirect owners."},{"field":"price","element":"transactionPricePerShare","label":"F4","text":"On May 16, 2025, Derby Investor distributed 235,397 shares of Common Stock to one or more of its members or partners in connection with certain charitable gifts made by such members or partners or their direct or indirect owners."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Bain Capital Investors, LLC (\"BCI\") is the manager of Bain Capital Partners XI, L.P. (\"Partners XI\"), which is the general partner of Bain Capital Fund XI, L.P. (\"Fund XI\"). Fund XI is the (i) sole member of BCPE Derby GP, LLC (\"Derby GP\"), which is the general partner of BCPE Derby Investor, LP (\"Derby Investor\") and (ii) sole member of BCPE Derby (DE) SPV, LLC (\"Derby SPV GP\"), which is the general partner of BCPE Derby (DE) SPV, LP (\"Derby SPV Investor\" and, together with BCI, Partners XI, Fund XI, Derby GP, Derby Investor and Derby SPV GP, the \"Bain Capital Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"(Continued from footnote 1) As a result, the Bain Capital Entities may be deemed to share voting and dispositive power with respect to the shares of the Issuer's common stock, par value $0.01 per share (the \"Common Stock\"), held by Derby Investor and Derby SPV Investor. The Bain Capital Entities disclaim beneficial ownership of such securities, except to the extent of their pecuniary interest therein."}],"balance_after":18506886,"source":{"system":"sec-edgar","filing":"0000950170-25-075513","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1040508/000095017025075513/ownership.xml","form_type":"4"}},{"id":1141602,"issuer":{"id":1420,"kind":"organization","name":"Waystar Holding Corp.","symbol":"WAY"},"owners":[{"id":52008,"kind":"organization","name":"Bain Capital Investors LLC","position":1,"cik":"0001040508","reported_name":"BAIN CAPITAL INVESTORS LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75354,"kind":"organization","name":"BCPE Derby Investor, LP","position":2,"cik":"0002025342","reported_name":"BCPE Derby Investor, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75355,"kind":"organization","name":"BCPE Derby GP, LLC","position":3,"cik":"0002025234","reported_name":"BCPE Derby GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75356,"kind":"organization","name":"Bain Capital Fund XI, L.P.","position":4,"cik":"0001568889","reported_name":"Bain Capital Fund XI, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75357,"kind":"organization","name":"Bain Capital Partners XI, L.P.","position":5,"cik":"0001851748","reported_name":"Bain Capital Partners XI, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75358,"kind":"organization","name":"BCPE Derby (DE) SPV, LP","position":6,"cik":"0002048434","reported_name":"BCPE Derby (DE) SPV, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75359,"kind":"organization","name":"BCPE Derby (DE) SPV (GP), LLC","position":7,"cik":"0002048242","reported_name":"BCPE Derby (DE) SPV (GP), LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock, par value $0.01 per share","published_at":"2025-05-21T00:55:01.000Z","date":"2025-05-16","kind":"sale","planned":false,"acquired":false,"shares":3012253,"price":37.39,"value":112628139.67,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F3","text":"Pursuant to a registered public offering that closed on May 16, 2025, 233,925 shares of Common Stock were sold by Derby Investor and 2,778,328 shares of Common Stock were sold by Derby SPV Investor at a price of $37.3937 (net of underwriting discount)."},{"field":"price","element":"transactionPricePerShare","label":"F3","text":"Pursuant to a registered public offering that closed on May 16, 2025, 233,925 shares of Common Stock were sold by Derby Investor and 2,778,328 shares of Common Stock were sold by Derby SPV Investor at a price of $37.3937 (net of underwriting discount)."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Bain Capital Investors, LLC (\"BCI\") is the manager of Bain Capital Partners XI, L.P. 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The Bain Capital Entities disclaim beneficial ownership of such securities, except to the extent of their pecuniary interest therein."}],"balance_after":18742283,"source":{"system":"sec-edgar","filing":"0000950170-25-075513","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1040508/000095017025075513/ownership.xml","form_type":"4"}},{"id":1245011,"issuer":{"id":1420,"kind":"organization","name":"Waystar Holding Corp.","symbol":"WAY"},"owners":[{"id":52008,"kind":"organization","name":"Bain Capital Investors LLC","position":1,"cik":"0001040508","reported_name":"BAIN CAPITAL INVESTORS LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75354,"kind":"organization","name":"BCPE Derby Investor, LP","position":2,"cik":"0002025342","reported_name":"BCPE Derby Investor, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75355,"kind":"organization","name":"BCPE Derby GP, LLC","position":3,"cik":"0002025234","reported_name":"BCPE Derby GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75356,"kind":"organization","name":"Bain Capital Fund XI, L.P.","position":4,"cik":"0001568889","reported_name":"Bain Capital Fund XI, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75357,"kind":"organization","name":"Bain Capital Partners XI, L.P.","position":5,"cik":"0001851748","reported_name":"Bain Capital Partners XI, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75358,"kind":"organization","name":"BCPE Derby (DE) SPV, LP","position":6,"cik":"0002048434","reported_name":"BCPE Derby (DE) SPV, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75359,"kind":"organization","name":"BCPE Derby (DE) SPV (GP), LLC","position":7,"cik":"0002048242","reported_name":"BCPE Derby (DE) SPV (GP), LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock, par value $0.01 per share","published_at":"2025-02-27T01:00:22.000Z","date":"2025-02-24","kind":"other","planned":false,"acquired":false,"shares":573192,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F4","text":"On February 24, 2025, Derby Investor distributed 347,013 shares of Common Stock and Derby SPV Investor distributed 226,179 shares of Common Stock to one or more of their respective members or partners in connection with certain charitable gifts made by such members or partners or their direct or indirect owners."},{"field":"price","element":"transactionPricePerShare","label":"F4","text":"On February 24, 2025, Derby Investor distributed 347,013 shares of Common Stock and Derby SPV Investor distributed 226,179 shares of Common Stock to one or more of their respective members or partners in connection with certain charitable gifts made by such members or partners or their direct or indirect owners."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Bain Capital Investors, LLC (\"BCI\") is the manager of Bain Capital Partners XI, L.P. (\"Partners XI\"), which is the general partner of Bain Capital Fund XI, L.P. (\"Fund XI\"). Fund XI is the (i) sole member of BCPE Derby GP, LLC (\"Derby GP\"), which is the general partner of BCPE Derby Investor, LP (\"Derby Investor\") and (ii) sole member of BCPE Derby (DE) SPV, LLC (\"Derby SPV GP\"), which is the general partner of BCPE Derby (DE) SPV, LP (\"Derby SPV Investor\" and, together with BCI, Partners XI, Fund XI, Derby GP, Derby Investor and Derby SPV GP, the \"Bain Capital Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"(Continued from footnote 1) As a result, the Bain Capital Entities may be deemed to share voting and dispositive power with respect to the shares of the Issuer's common stock, par value $0.01 per share (the \"Common Stock\"), held by Derby Investor and Derby SPV Investor. The Bain Capital Entities disclaims beneficial ownership of such securities, except to the extent of their pecuniary interest therein."}],"balance_after":21754536,"source":{"system":"sec-edgar","filing":"0000950170-25-028174","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1040508/000095017025028174/ownership.xml","form_type":"4"}},{"id":1245010,"issuer":{"id":1420,"kind":"organization","name":"Waystar Holding Corp.","symbol":"WAY"},"owners":[{"id":52008,"kind":"organization","name":"Bain Capital Investors LLC","position":1,"cik":"0001040508","reported_name":"BAIN CAPITAL INVESTORS LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75354,"kind":"organization","name":"BCPE Derby Investor, LP","position":2,"cik":"0002025342","reported_name":"BCPE Derby Investor, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75355,"kind":"organization","name":"BCPE Derby GP, LLC","position":3,"cik":"0002025234","reported_name":"BCPE Derby GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75356,"kind":"organization","name":"Bain Capital Fund XI, L.P.","position":4,"cik":"0001568889","reported_name":"Bain Capital Fund XI, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75357,"kind":"organization","name":"Bain Capital Partners XI, L.P.","position":5,"cik":"0001851748","reported_name":"Bain Capital Partners XI, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75358,"kind":"organization","name":"BCPE Derby (DE) SPV, LP","position":6,"cik":"0002048434","reported_name":"BCPE Derby (DE) SPV, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75359,"kind":"organization","name":"BCPE Derby (DE) SPV (GP), LLC","position":7,"cik":"0002048242","reported_name":"BCPE Derby (DE) SPV (GP), LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock, par value $0.01 per share","published_at":"2025-02-27T01:00:22.000Z","date":"2025-02-24","kind":"sale","planned":false,"acquired":false,"shares":5652689,"price":38.6,"value":218193795.4,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F3","text":"Pursuant to a registered public offering that closed on February 24, 2025, 552,696 shares of Common Stock were sold by Derby Investor and 5,099,993 shares of Common Stock were sold by Derby SPV Investor at a price of $38.60 (net of underwriting discount)."},{"field":"price","element":"transactionPricePerShare","label":"F3","text":"Pursuant to a registered public offering that closed on February 24, 2025, 552,696 shares of Common Stock were sold by Derby Investor and 5,099,993 shares of Common Stock were sold by Derby SPV Investor at a price of $38.60 (net of underwriting discount)."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Bain Capital Investors, LLC (\"BCI\") is the manager of Bain Capital Partners XI, L.P. (\"Partners XI\"), which is the general partner of Bain Capital Fund XI, L.P. (\"Fund XI\"). Fund XI is the (i) sole member of BCPE Derby GP, LLC (\"Derby GP\"), which is the general partner of BCPE Derby Investor, LP (\"Derby Investor\") and (ii) sole member of BCPE Derby (DE) SPV, LLC (\"Derby SPV GP\"), which is the general partner of BCPE Derby (DE) SPV, LP (\"Derby SPV Investor\" and, together with BCI, Partners XI, Fund XI, Derby GP, Derby Investor and Derby SPV GP, the \"Bain Capital Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"(Continued from footnote 1) As a result, the Bain Capital Entities may be deemed to share voting and dispositive power with respect to the shares of the Issuer's common stock, par value $0.01 per share (the \"Common Stock\"), held by Derby Investor and Derby SPV Investor. The Bain Capital Entities disclaims beneficial ownership of such securities, except to the extent of their pecuniary interest therein."}],"balance_after":22327728,"source":{"system":"sec-edgar","filing":"0000950170-25-028174","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1040508/000095017025028174/ownership.xml","form_type":"4"}},{"id":1331766,"issuer":{"id":1420,"kind":"organization","name":"Waystar Holding Corp.","symbol":"WAY"},"owners":[{"id":52008,"kind":"organization","name":"Bain Capital Investors LLC","position":1,"cik":"0001040508","reported_name":"BAIN CAPITAL INVESTORS LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75354,"kind":"organization","name":"BCPE Derby Investor, LP","position":2,"cik":"0002025342","reported_name":"BCPE Derby Investor, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75355,"kind":"organization","name":"BCPE Derby GP, LLC","position":3,"cik":"0002025234","reported_name":"BCPE Derby GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75356,"kind":"organization","name":"Bain Capital Fund XI, L.P.","position":4,"cik":"0001568889","reported_name":"Bain Capital Fund XI, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75357,"kind":"organization","name":"Bain Capital Partners XI, L.P.","position":5,"cik":"0001851748","reported_name":"Bain Capital Partners XI, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Ordinary Shares, $0.01 par value","published_at":"2024-12-16T22:50:54.000Z","date":"2024-12-12","kind":"other","planned":false,"acquired":true,"shares":23936936,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F2","text":"On December 12, 2024, Derby SPV Investor received 23,936,936 shares of Common Stock (the \"Shares\") in a transaction that is exempt from Section 16 pursuant to Rule 16a-13, wherein Derby Investor distributed the Shares to Fund XI, and then Fund XI immediately contributed the Shares to Derby SPV Investor. Following the transaction, Derby Investor directly owns 4,043,481 shares and Derby SPV Investor directly owns 23,936,936 shares."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"On December 12, 2024, Derby SPV Investor received 23,936,936 shares of Common Stock (the \"Shares\") in a transaction that is exempt from Section 16 pursuant to Rule 16a-13, wherein Derby Investor distributed the Shares to Fund XI, and then Fund XI immediately contributed the Shares to Derby SPV Investor. Following the transaction, Derby Investor directly owns 4,043,481 shares and Derby SPV Investor directly owns 23,936,936 shares."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Bain Capital Fund XI, LP (\"Fund XI\") is the (i) sole member of BCPE Derby GP, LLC (\"Derby GP\"), which is the general partner of BCPE Derby Investor, LP (\"Derby Investor\"), and (ii) sole member of BCPE Derby (DE) SPV, LLC, (\"Derby SPV GP\"), which is the general partner of BCPE Derby (DE) SPV, LP (\"Derby SPV Investor\"). Bain Capital Investors, LLC (\"BCI\") is the manager of Bain Capital Partners XI, LP (\"Partners XI\" and, together with BCI, Derby GP, Derby Investor, Derby SPV GP, Derby SPV Investor and Fund XI, the \"Bain Capital Entities\"), which is the general partner of Fund XI. As a result, each of the Bain Capital Entities may be deemed to share voting and dispositive power with respect to the shares of Common Stock held by Derby Investor and Derby SPV Investor. Each of the Bain Capital Entities disclaims beneficial ownership of such securities, except to the extent of its pecuniary interest therein."}],"balance_after":27980417,"source":{"system":"sec-edgar","filing":"0000950170-24-136777","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1040508/000095017024136777/ownership.xml","form_type":"4"}},{"id":1331765,"issuer":{"id":1420,"kind":"organization","name":"Waystar Holding Corp.","symbol":"WAY"},"owners":[{"id":52008,"kind":"organization","name":"Bain Capital Investors LLC","position":1,"cik":"0001040508","reported_name":"BAIN CAPITAL INVESTORS LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75354,"kind":"organization","name":"BCPE Derby Investor, LP","position":2,"cik":"0002025342","reported_name":"BCPE Derby Investor, LP","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75355,"kind":"organization","name":"BCPE Derby GP, LLC","position":3,"cik":"0002025234","reported_name":"BCPE Derby GP, LLC","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75356,"kind":"organization","name":"Bain Capital Fund XI, L.P.","position":4,"cik":"0001568889","reported_name":"Bain Capital Fund XI, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":75357,"kind":"organization","name":"Bain Capital Partners XI, L.P.","position":5,"cik":"0001851748","reported_name":"Bain Capital Partners XI, L.P.","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Ordinary Shares, $0.01 par value","published_at":"2024-12-16T22:50:54.000Z","date":"2024-12-12","kind":"other","planned":false,"acquired":false,"shares":23936936,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F2","text":"On December 12, 2024, Derby SPV Investor received 23,936,936 shares of Common Stock (the \"Shares\") in a transaction that is exempt from Section 16 pursuant to Rule 16a-13, wherein Derby Investor distributed the Shares to Fund XI, and then Fund XI immediately contributed the Shares to Derby SPV Investor. Following the transaction, Derby Investor directly owns 4,043,481 shares and Derby SPV Investor directly owns 23,936,936 shares."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"On December 12, 2024, Derby SPV Investor received 23,936,936 shares of Common Stock (the \"Shares\") in a transaction that is exempt from Section 16 pursuant to Rule 16a-13, wherein Derby Investor distributed the Shares to Fund XI, and then Fund XI immediately contributed the Shares to Derby SPV Investor. Following the transaction, Derby Investor directly owns 4,043,481 shares and Derby SPV Investor directly owns 23,936,936 shares."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Bain Capital Fund XI, LP (\"Fund XI\") is the (i) sole member of BCPE Derby GP, LLC (\"Derby GP\"), which is the general partner of BCPE Derby Investor, LP (\"Derby Investor\"), and (ii) sole member of BCPE Derby (DE) SPV, LLC, (\"Derby SPV GP\"), which is the general partner of BCPE Derby (DE) SPV, LP (\"Derby SPV Investor\"). Bain Capital Investors, LLC (\"BCI\") is the manager of Bain Capital Partners XI, LP (\"Partners XI\" and, together with BCI, Derby GP, Derby Investor, Derby SPV GP, Derby SPV Investor and Fund XI, the \"Bain Capital Entities\"), which is the general partner of Fund XI. As a result, each of the Bain Capital Entities may be deemed to share voting and dispositive power with respect to the shares of Common Stock held by Derby Investor and Derby SPV Investor. Each of the Bain Capital Entities disclaims beneficial ownership of such securities, except to the extent of its pecuniary interest therein."}],"balance_after":4043481,"source":{"system":"sec-edgar","filing":"0000950170-24-136777","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1040508/000095017024136777/ownership.xml","form_type":"4"}}]}