After spending last week hyping Grok's spicy new features, Elon Musk kicked off this week by threatening to sue Apple for supposedly gaming the App Store rankings to favor ChatGPT over Grok.
"Apple is behaving in a manner that makes it impossible for any AI company besides OpenAI to reach #1 in the App Store, which is an unequivocal antitrust violation," Musk wrote on X, without providing any evidence. "xAI will take immediate legal action."
In another post, Musk tagged Apple, asking, "Why do you refuse to put either X or Grok in your 'Must Have' section when X is the #1 news app in the world and Grok is #5 among all apps?"
"Are you playing politics?" Musk asked. "What gives? Inquiring minds want to know."
Apple did not respond to the post and has not responded to Ars' request to comment.
At the heart of Musk's complaints is an OpenAI partnership that Apple announced last year, integrating ChatGPT into versions of its iPhone, iPad, and Mac operating systems.
Musk has alleged that this partnership incentivized Apple to boost ChatGPT rankings. OpenAI's popular chatbot "currently holds the top spot in the App Store's 'Top Free Apps' section for iPhones in the US," Reuters noted, "while xAI's Grok ranks fifth and Google’s Gemini chatbot sits at 57th." Sensor Tower data shows ChatGPT similarly tops Google Play Store rankings.
While Musk seems insistent that ChatGPT is artificially locked in the lead, fact-checkers on X added a community note to his post. They confirmed that at least one other AI tool has somewhat recently unseated ChatGPT in the US rankings. Back in January, DeepSeek topped App Store charts and held the lead for days, ABC News reported.
OpenAI did not immediately respond to Ars' request to comment on Musk's allegations, but an OpenAI developer, Steven Heidel, did add a quip in response to one of Musk's posts, writing, "Don't forget to also blame Google for OpenAI being #1 on Android, and blame SimilarWeb for putting ChatGPT above X on the most-visited websites list, and blame...."
Musk pulls Apple into OpenAI battle
It seems possible that Musk is attacking Apple as a publicity stunt to get more people to check out Grok as supposedly secretly deserving of the top spot in the App Store. Musk may also be exploring an antitrust claim due to Apple's recent struggles defending against accusations that its App Store is anticompetitive in both the European Union and the US.
But considering Musk's long-time beef with OpenAI—which he has sued for allegedly making a "fool" out of him by convincing him to invest early on with a false promise to always remain a non-profit—the accusations could be linked to his ire over OpenAI using his money to beat him to releasing a more popular chatbot.
It's currently not clear where Musk's legal fight is going. Most recently in that litigation, OpenAI has accused Musk of largely refusing to take part in discovery, allegedly using delay tactics to keep OpenAI from raising a defense against Musk's claims. Musk apparently won't even share his own emails from his own companies, which must have been a predictable ask when he filed the lawsuit, in defiance of a judge's order, OpenAI alleged.
OpenAI has suggested that Musk is guilty of "substantial bad-faith conduct" in the litigation, which they alleged is part of a "campaign of harassment, interference, and misinformation designed to take down OpenAI and clear the field for himself."
In the filing, they point to Musk seeking to give himself "sole control" of a for-profit restructuring of OpenAI back in 2017 as evidence that Musk was supposedly never fully invested in OpenAI's original non-profit mission that he now appears to be urgently defending. Further, Musk allegedly tried to convince OpenAI to make a for-profit pivot in 2018 by letting Tesla absorb the company. That, Musk allegedly hoped, would have turned Tesla into OpenAI's "cash cow," the filing said.
As more recent evidence of allegedly bad-faith conduct, OpenAI noted that Musk signed a letter calling for a moratorium on all AI development in 2023. That six-month pause on all AI development may have bought Musk time to catch up with ChatGPT, as he was at that time plowing ahead with his plans to release Grok, OpenAI alleged, questioning the sincerity of Musk's co-signing of the letter.
And finally, in 2025, OpenAI flagged Musk's allegedly "sham bid" to buy OpenAI for $97 billion "as a 'naked effort to disrupt the [OpenAI] board’s consideration of a potential restructuring and to sow confusion among employees and potential investors,' for the ultimate purpose of threatening 'OpenAI’s ability to pursue its mission on terms uncorrupted by unlawful harassment and interference.'"
All of this "deceptive conduct," OpenAI alleged, shows that Musk has "unclean hands," and his "supposed grievances are not genuinely held."
As the lawsuit moves forward, discovery is scheduled to end in December, giving OpenAI four months to prod Musk for the evidence they claim to need to raise these defenses and more. In the meantime, Musk apparently is mulling filing a new complaint against Apple that could lead to additional attacks on OpenAI's business.
Perhaps most damning for Musk, however, OpenAI is attempting to subpoena Musk's lawyer, Marc Toberoff, who, it claims, "played a key role in coordinating Musk’s sham bid for OpenAI—including by hastily soliciting numerous third parties to participate in the supposed hostile takeover." If OpenAI beats the lawsuit, it could be a major blow to Musk's ego as he seeks to dominate the AI industry by outperforming his former partner. Most recently, Musk vowed that Grok 5 will soon outperform OpenAI's GPT-5.
But if Musk pulls out a win, any "unlawful benefits" that OpenAI received as a result of Musk's early investment could be disgorged, perhaps hobbling OpenAI just as xAI receives funding to continue building out "the world’s biggest supercomputer, Colossus," to supercharge Grok.
xAI did not respond to Ars' request to comment.
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