Summary
In a late-night blog post last Friday, OpenAI said it would wind down its partnership with Cursor, the startup behind one of the most popular AI coding tools on the market. The reason OpenAI gave for the decision is effectively that it can’t trust Elon Musk, whose company SpaceX recently acquired Cursor in a 60billiondeal.Indoingso,OpenAIwalkedawayfromoneofitsmostimportantcustomers.CursorhaslongpaidOpenAIfeestooffertheChatGPT−maker’smodelstodevelopersusingitsAIcodingeditor.Atthestartof2026,CursorwasoneofOpenAI’stopfivecustomersintermsofrevenue,peoplefamiliarwiththemattertellWIRED.Bythespringofthisyear,OpenAIestimatedCursorwouldbringinmorethan1 billion in annualized revenue for the ChatGPT maker, based on the partnership’s performance at that time, the people said.
The figures, which have not been previously reported, indicate the financial loss OpenAI is willing to take on to avoid doing business with Musk. OpenAI declined to comment. Representatives for SpaceX and Cursor did not immediately respond to WIRED’s request for comment.
“We are making this choice because we cannot be confident that SpaceX will use our technology within our terms of service, based on our experience with Elon Musk’s companies violating contracts,” said OpenAI in the blog post.
As OpenAI prepares to go public next year, it’s trying to show investors a more stable business—ideally one that doesn’t rely so heavily on the goodwill of Musk. OpenAI reportedly now generates more than 40billion](https://www.bloomberg.com/news/articles/2026−08−13/openai−s−revenue−run−rate−tops−40−billion−ahead−of−ipo)inannualizedrevenue,drawingonseveraldifferentlinesofbusiness,includingsubscriptions,adsinChatGPT,andsellingaccesstoitsAIcodingtool,Codex.LosingamajorcustomerlikeCursormaynothurtOpenAIfinanciallyasmuchasitoncewouldhave,butitwascertainlyadifficultdecision.Thecompanyacknowledgedinitsblogpostthatendingthepartnershipmaydamageitsstandingwithdevelopers—acommunityithasspentyearscarefullyworkingtowinover—bycuttingoffamajorchanneltheyusetoaccessOpenAI’smodels.MichaelTruell,Cursor’sfounderandCEO,whoisnowleadingteamsatSpaceX,respondedpubliclytoOpenAI’sannouncementhourslateronFridayina[postonX](https://x.com/mntruell/status/2093532254006063557?s=20),claimingthattheChatGPT−maker’smodelsonly“serveabout5OpenAI’sheadofcoreproducts,ThibaultSottiaux,wasquickto[pointout](https://x.com/thsottiaux/status/2093784314714657110?s=20)thattokenusageis“notaproxyforrevenuenorvaluecreated,”andaskedTruellto“sharethemath”behindthe5percentnumber.WIREDpreviouslyreportedthatCursorleadershopedto[remainaplatform](https://www.wired.com/story/can−cursor−remain−an−open−platform−inside−of−spacex/)forthird−partyAImodelsfromOpenAIandAnthropic,evenaftertheSpaceXacquisition.SomeAIinsidersconsideredthatwishfulthinking,assumingthatCursorandOpenAI’sbreakuphaslongbeenaforegoneconclusion.AsOpenAIbuildsCodexintoalargeAIcodingbusiness,itincreasinglyfindsitselfcompetingwithCursorforcustomers.Nevertheless,thecompanieshaveoperatedrelativelypeacefully,aspartnersandcompetitors,forwelloverayear.Evidently,thatarrangementwasnolongerpossiblewithMuskincontrolofCursor.OpenAImayhavedeterminedthatitsCursorpartnershipwasnotworththeriskthatSpaceXmightdistillitsbestAImodels.Thecompanynotedinitsblogpostthat,earlierthisyear,MuskseeminglysaidthatxAI—nowapartofSpaceX—[usedOpenAI’smodelstotrainitsown](https://www.wired.com/story/elon−musk−distill−openai−models−partly−xai/).TheapparentadmissioncameduringMusk’sdepositioninhislawsuitagainstOpenAI,inwhichheclaimedthatSamAltmanandGregBrockmanhad[stolenacharity](https://www.wired.com/story/musk−v−altman−trial−openai−xai/)theycreatedtogetherroughlyadecadeago.Afederaljurydismissedthesuitearlierthisyear.OpenAIandCursorhavealong,complicatedhistoryoftheirown.OpenAI’sstartupfundwasoneofthefirstinvestorsinCursor,participatinginits2023seedround.Atthetime,theideathatayoungstartupcouldcompetewithMicrosoft’spopularAIcodingtool,GitHubCopilot,seemedlikeapipedream.Butintheyearssince,[Cursor’spopularitywithdevelopers](https://www.wired.com/story/why−did−a−10−billion−dollar−startup−let−me−vibe−code−for−them−and−why−did−i−love−it/)becameundeniable.WIREDpreviouslyreportedthatOpenAI[approachedCursoraboutanacquisition](https://www.wired.com/story/openai−codex−race−claude−code/)atonepoint,thoughthetalksneverreachedanadvancedstage.Bythesummerof2025,TruellappearedprominentlyinOpenAI’smarketingmaterialsforthelaunchofitslongawaitedGPT−5AImodel.Cursorisn’tdonewiththird−partyAImodelsjustyet.InthewakeofOpenAI’sannouncement,AnthropiccofounderTomBrownsaidhiscompanywouldcontinueto[makeClaudemodelsavailable](https://x.com/NotTomBrown/status/2093541294027280657?s=20)inCursor.I’mnotsurethat’soutofthegoodnessoftheirheart—AnthropicmayhavetoplaynicewithCursorbecauseitdependsonMusk’sSpaceXfor[45 billion of data center capacity. Last year, Anthropic had no problem cutting off the AI coding startup called Windsurf when OpenAI was rumored to be acquiring it. (Windsurf was ultimately bought by another startup, Cognition.) At the time, Anthropic cofounder Jared Kaplan told me, “It would be odd for us to sell Claude to OpenAI.”
I guess it’s fine to sell Claude to SpaceX, though?
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By Maxwell Zeff
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