Apple is escalating its legal fight against OpenAI, asking a federal judge to immediately block the artificial intelligence company from accessing or using what it claims are stolen trade secrets tied to its hardware business. OpenAI has forcefully rejected the allegations, accusing Apple of making major factual errors—including sending a legal warning to the wrong executive.

In a filing submitted Monday, Apple requested a preliminary injunction preventing OpenAI and two former Apple employees from using, disclosing, or benefiting from confidential information that the iPhone maker alleges was improperly taken. Apple argued that without immediate court intervention, it faces irreparable harm.

OpenAI responded within hours with a sharply worded blog post describing Apple’s lawsuit as “careless, aggressive and oddly personal,” while disputing the company’s version of events.

Apple had previously claimed it warned OpenAI about the alleged theft in February but received no response. OpenAI denied that assertion and said Apple has since acknowledged that its outside attorneys mistakenly contacted the wrong person.

“Apple had claimed that they contacted OpenAI in February and that we didn’t respond. They now admit that their outside lawyers emailed the wrong person after confusing two Asian last names — only after we brought this to their attention,” OpenAI said.

According to emails released by OpenAI, attorney Gabriel Gross of the law firm Weil, Gotshal & Manges mistakenly sent a warning letter to OpenAI General Counsel Che Chang instead of a former Apple employee whose last name was Wang.

The correspondence also included a reference to a telephone conversation that OpenAI says never occurred. According to the company, Apple later withdrew that claim after the mistake was pointed out.

OpenAI said Chang replied by forwarding the email to Apple’s legal department, explaining that he had never spoken with Gross and had no idea who he was.

Gross later apologized for the error and indicated that Wang had agreed to cooperate. OpenAI said Apple then took no further action for five months before filing suit.

Apple launched the lawsuit on July 10 in federal court in Northern California, accusing OpenAI of orchestrating a coordinated effort to obtain confidential hardware information as it develops its first consumer device.

The complaint names former Apple senior system electrical engineer Chang Liu and former Apple vice president of product design Tang Yew Tan, who spent years overseeing products including the iPhone and Apple Watch before joining OpenAI to lead its hardware division.

Apple alleges Liu copied dozens of confidential hardware documents after leaving the company by using another employee’s laptop. It also claims Tan emailed supplier information to his personal account and advised departing employees on how to avoid scrutiny during Apple’s exit procedures.

OpenAI has rejected those allegations, insisting it possesses no Apple trade secrets and has no interest in acquiring them.

The company also published internal iMessage conversations that it says contradict Apple’s claims. According to OpenAI, the messages show Apple employees repeatedly contacting Liu after he had left the company, asking for help locating technical files and other information. One former colleague even joked that Liu remained “the best” source, “even if you don’t work here anymore.”

OpenAI argued that any continued access to Apple systems resulted from Apple’s own employee offboarding process, which it claims allowed former workers to retain access they neither requested nor expected.

Regarding Tan, OpenAI said the longtime Apple executive has consistently instructed his team not to use confidential information belonging to previous employers.

Apple is also seeking expedited discovery, asking the court to quickly order depositions of Liu, Tan, OpenAI employee Yu-Ting Peng, and another former Apple employee whose identity has not been disclosed.

In its court filing, Apple argued, “Apple will be irreparably harmed absent a preliminary injunction.”

OpenAI said it is willing to comply with three of Apple’s five requested restrictions, including prohibiting future access to any Apple confidential information, refraining from using such material, and preserving relevant evidence. However, the company opposes Apple’s request to allow its lawyers and forensic investigators to inspect OpenAI’s computers, storage devices, and internal networks.

The legal battle carries enormous implications for both companies. More than 400 former Apple employees have joined OpenAI, which industry analysts believe is developing an AI-powered consumer device that could eventually compete directly with smartphones—and potentially challenge the iPhone’s dominant position in the marketplace.

The dispute marks another major courtroom battle for OpenAI, which earlier this year successfully defeated a separate legal challenge brought by Elon Musk’s xAI.