{"cik":"0001889441","entityType":"other","sic":"","sicDescription":"","ownerOrg":null,"insiderTransactionForOwnerExists":0,"insiderTransactionForIssuerExists":0,"name":"What If VC Blackrock 21 a Series of What If Ventures Master LLC","tickers":[],"exchanges":[],"ein":"872921548","lei":null,"description":"","website":"","investorWebsite":"","category":"","fiscalYearEnd":"1231","stateOfIncorporation":"DE","stateOfIncorporationDescription":"DE","addresses":{"mailing":{"street1":"2093 PHILADELPHIA PIKE","street2":"5885","city":"CLAYMONT","stateOrCountry":"DE","zipCode":"19703","stateOrCountryDescription":"DE","isForeignLocation":null,"foreignStateTerritory":null,"country":null,"countryCode":null},"business":{"street1":"2093 PHILADELPHIA PIKE","street2":"5885","city":"CLAYMONT","stateOrCountry":"DE","zipCode":"19703","stateOrCountryDescription":"DE","isForeignLocation":null,"foreignStateTerritory":null,"country":null,"countryCode":null}},"phone":"(360) 946-0604","flags":"","formerNames":[],"filings":{"recent":{"accessionNumber":["0001889441-21-000001"],"filingDate":["2021-11-08"],"reportDate":[""],"acceptanceDateTime":["2021-11-08T22:22:38.000Z"],"act":["33"],"form":["D"],"fileNumber":["021-420330"],"filmNumber":["211388974"],"items":["06b,3C,3C.1"],"core_type":["D"],"size":[7306],"isXBRL":[0],"isInlineXBRL":[0],"isXBRLNumeric":[null],"primaryDocument":["xslFormDX01/primary_doc.xml"],"primaryDocDescription":[""]},"files":[]}}