{"cik":"0001590973","entityType":"other","sic":"","sicDescription":"","ownerOrg":"","insiderTransactionForOwnerExists":1,"insiderTransactionForIssuerExists":0,"name":"Flagship Ventures Fund IV-Rx, L.P.","tickers":[],"exchanges":[],"ein":"453977297","lei":null,"description":"","website":"","investorWebsite":"","category":"","fiscalYearEnd":"1231","stateOfIncorporation":"DE","stateOfIncorporationDescription":"DE","addresses":{"mailing":{"street1":"55 CAMBRIDGE PARKWAY, 8TH FLOOR","street2":null,"city":"CAMBRIDGE","stateOrCountry":"MA","zipCode":"02142","stateOrCountryDescription":"MA","isForeignLocation":null,"foreignStateTerritory":null,"country":null,"countryCode":null},"business":{"street1":"55 CAMBRIDGE PARKWAY, 8TH FLOOR","street2":null,"city":"CAMBRIDGE","stateOrCountry":"MA","zipCode":"02142","stateOrCountryDescription":"MA","isForeignLocation":null,"foreignStateTerritory":null,"country":null,"countryCode":null}},"phone":"617-868-1888","flags":"","formerNames":[],"filings":{"recent":{"accessionNumber":["0001968582-24-001180","0000899243-22-020533","0000899243-22-011535","0000899243-21-004962","0000899243-20-032200","0000899243-20-022975","0000899243-20-018150","0000899243-20-014188","0000899243-20-013708","0000899243-20-013020","0000899243-19-028975","0001104659-19-029735","0001104659-19-027935","0000899243-18-030859","0000899243-18-030428","0001104659-18-046534","0001104659-18-045601","0000899243-18-013014","0000899243-18-011976","0001012975-17-000639","0001012975-16-001507","0001012975-16-001505","0001012975-16-001503","0001012975-16-001495","0001012975-16-001437","0001104659-16-131412","0001104659-16-130203","0001012975-16-001264","0001179110-16-018859","0001179110-16-018336","0001209191-15-057204","0001209191-15-056411","0001181431-14-006845","0001181431-14-005334"],"filingDate":["2024-12-13","2022-06-01","2022-03-18","2021-02-04","2020-11-25","2020-08-19","2020-07-01","2020-05-26","2020-05-20","2020-05-13","2019-12-11","2019-05-15","2019-05-08","2018-12-13","2018-12-07","2018-07-23","2018-07-17","2018-05-15","2018-05-08","2017-08-21","2016-09-26","2016-09-21","2016-09-16","2016-09-08","2016-08-15","2016-07-07","2016-06-29","2016-05-27","2016-02-09","2016-02-02","2015-06-29","2015-06-25","2014-02-13","2014-02-05"],"reportDate":["","2022-05-27","2022-03-16","2021-02-02","2020-11-23","2020-08-17","2020-06-29","2020-05-21","2020-05-18","2020-05-11","2019-12-09","2019-05-13","2019-05-08","2018-12-11","2018-12-07","2018-07-20","2018-07-17","2018-05-11","2018-05-08","2017-08-17","2016-09-22","2016-09-19","2016-09-14","2016-09-06","2016-08-11","2016-07-06","2016-06-29","2016-05-25","2016-02-08","2016-02-02","2015-06-25","2015-06-25","2014-02-11","2014-02-05"],"acceptanceDateTime":["2024-12-13T21:08:54.000Z","2022-06-01T23:00:17.000Z","2022-03-18T12:30:12.000Z","2021-02-04T22:56:12.000Z","2020-11-25T23:00:45.000Z","2020-08-20T00:15:11.000Z","2020-07-01T21:24:51.000Z","2020-05-26T21:00:26.000Z","2020-05-20T21:15:24.000Z","2020-05-13T22:12:12.000Z","2019-12-12T00:38:35.000Z","2019-05-15T20:18:59.000Z","2019-05-09T01:20:04.000Z","2018-12-13T21:20:14.000Z","2018-12-07T22:53:16.000Z","2018-07-23T20:34:53.000Z","2018-07-18T00:49:43.000Z","2018-05-16T00:43:24.000Z","2018-05-09T00:17:45.000Z","2017-08-21T20:19:58.000Z","2016-09-26T20:03:34.000Z","2016-09-21T21:37:33.000Z","2016-09-16T20:15:53.000Z","2016-09-08T22:53:37.000Z","2016-08-15T21:22:35.000Z","2016-07-07T10:04:02.000Z","2016-06-29T23:48:06.000Z","2016-05-27T22:43:31.000Z","2016-02-09T23:08:58.000Z","2016-02-02T23:17:31.000Z","2015-06-29T21:59:44.000Z","2015-06-25T21:37:20.000Z","2014-02-13T23:55:22.000Z","2014-02-06T00:17:30.000Z"],"act":["","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34","34"],"form":["144","4","4","4","4","4","4","4","4","4","4","4","3","4","3","4","3","4","3","4","4","4","4","4","4","4","3","4","4","3","4","3","4","3"],"fileNumber":["","001-38473","001-38901","001-38473","001-37465","001-38753","001-38473","001-38753","001-38901","001-38753","001-38753","001-38901","001-38901","001-38753","001-38753","001-38586","001-38586","001-38473","001-38473","001-37813","001-36296","001-36296","001-36296","001-36296","001-37687","001-37813","001-37813","001-37465","001-37687","001-37687","001-37465","001-37465","001-36296","001-36296"],"filmNumber":["","22988798","22751131","21592505","201352268","201118445","201006140","20911543","20898984","20874687","191280787","19828470","19808544","181233428","181224469","18964786","18957570","18838587","18816382","171043327","161902323","161896311","161889581","161877472","161834020","161755495","161740142","161683559","161401434","161382386","15959505","15952597","14608647","14577615"],"items":["","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","",""],"core_type":["144","4","4","4","4","4","4","4","4","4","4","4","3","4","3","4","3","4","3","4","4","4","4","4","4","4","3","4","4","3","4","3","4","3"],"size":[5696,35832,21264,31696,34289,18674,28406,43718,20971,18762,32542,68704,37412,50183,33058,59778,32026,31275,22268,21264,29085,25549,22065,24461,18280,51186,25303,30755,32677,18718,40456,26042,33721,22586],"isXBRL":[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],"isInlineXBRL":[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],"isXBRLNumeric":[null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null],"primaryDocument":["xsl144X01/primary_doc.xml","xslF345X03/doc4.xml","xslF345X03/doc4.xml","xslF345X03/doc4.xml","xslF345X03/doc4.xml","xslF345X03/doc4.xml","xslF345X03/doc4.xml","xslF345X03/doc4.xml","xslF345X03/doc4.xml","xslF345X03/doc4.xml","xslF345X03/doc4.xml","xslF345X03/a4.xml","xslF345X02/a3.xml","xslF345X03/doc4.xml","xslF345X02/doc3.xml","xslF345X03/a4.xml","xslF345X02/a3.xml","xslF345X03/doc4.xml","xslF345X02/doc3.xml","xslF345X03/edgar.xml","xslF345X03/edgar.xml","xslF345X03/edgar.xml","xslF345X03/edgar.xml","xslF345X03/edgar.xml","xslF345X03/edgar.xml","xslF345X03/a4.xml","xslF345X02/a3.xml","xslF345X03/edgar.xml","xslF345X03/edgar.xml","xslF345X02/edgar.xml","xslF345X03/doc4.xml","xslF345X02/doc3.xml","xslF345X03/rrd402098.xml","xslF345X02/rrd401014.xml"],"primaryDocDescription":["","FORM 4 SUBMISSION","FORM 4 SUBMISSION","FORM 4 SUBMISSION","FORM 4 SUBMISSION","FORM 4 SUBMISSION","FORM 4 SUBMISSION","FORM 4 SUBMISSION","FORM 4 SUBMISSION","FORM 4 SUBMISSION","FORM 4 SUBMISSION","4","3","FORM 4 SUBMISSION","FORM 3 SUBMISSION","4","3","FORM 4 SUBMISSION","FORM 3 SUBMISSION","PRIMARY DOCUMENT","PRIMARY DOCUMENT","PRIMARY DOCUMENT","PRIMARY DOCUMENT","PRIMARY DOCUMENT","PRIMARY DOCUMENT","4","3","PRIMARY DOCUMENT","FORM 4 -","FORM 3 -","FORM 4 SUBMISSION","FORM 3 SUBMISSION","FORM 4","FORM 3"]},"files":[]}}