Apple Escalates Legal Battle Against OpenAI With Preservation Letters Sent to Dozens of Former Employees

Apple has intensified its legal campaign against OpenAI by issuing formal preservation letters to approximately 40 former employees who have transitioned from the tech giant to the artificial intelligence startup. This move signals a significant escalation in a high-stakes trade secret lawsuit, as Apple seeks to safeguard its proprietary hardware engineering and product development secrets. The legal notices, which demand that recipients preserve all potentially relevant documents and communications, suggest that Apple believes the alleged misappropriation of confidential information is far more extensive than initially detailed in its original complaint.

The issuance of these letters follows a lawsuit filed by Apple in July 2026, which accuses OpenAI of orchestrating a systematic and coordinated effort to siphon off sensitive trade secrets. Apple contends that this intellectual property theft was facilitated by the recruitment of high-level engineers and executives who possessed intimate knowledge of Apple’s long-term hardware roadmap. By targeting a broader group of former employees with preservation notices, Apple is signaling its intent to conduct an exhaustive discovery process, searching for evidence of a "culture of misappropriation" within the ranks of those who moved from Cupertino to San Francisco.

The Core of the Allegations: Hardware Secrets and Proprietary Innovation

At the heart of Apple’s legal challenge is the claim that OpenAI has unfairly benefited from Apple’s multi-billion dollar investments in hardware research and development. Specifically, the lawsuit alleges that OpenAI has utilized proprietary designs, manufacturing processes, and internal technical specifications to accelerate its own hardware initiatives. While OpenAI is primarily known for its Large Language Models (LLMs) and software-based AI services, the company has recently made aggressive strides into the hardware sector, aiming to develop dedicated AI devices that could potentially disrupt the smartphone and personal computing markets.

Apple’s complaint argues that the information allegedly taken includes trade secrets related to thermal management in compact devices, specialized battery chemistry, and the integration of neural processing units (NPUs) within custom silicon. These technologies are critical to the performance of modern mobile devices and are areas where Apple has historically maintained a competitive edge. The company asserts that the loss of this information provides OpenAI with an "unearned and unlawful head start" in the race to define the next generation of consumer electronics.

Key Figures: The Defection of Tang Tan and Chang Liu

The lawsuit highlights the departures of several high-profile individuals as central to the alleged misconduct. Most notable among these is Tang Tan, who currently serves as OpenAI’s Chief Hardware Officer. Tan is a 24-year veteran of Apple, where he led product design for some of the company’s most iconic devices, including the iPhone and Apple Watch. His role at Apple gave him unprecedented access to the company’s most secretive future projects and manufacturing strategies.

Joining Tan is Chang Liu, another former Apple engineer who now serves on OpenAI’s hardware team. At Apple, Liu was a senior system electrical engineer, a role that involved the intricate design of circuitry and power systems. Apple’s legal team argues that the hiring of these specific individuals was not merely a matter of competitive recruitment but a strategic effort to acquire the blueprints of Apple’s hardware success.

The lawsuit includes claims for breach of contract against both Tan and Liu, alleging they violated their employment agreements which strictly prohibited the disclosure of trade secrets or the use of proprietary knowledge for the benefit of a competitor. Apple asserts that these individuals, along with dozens of others, were incentivized to bring "insider knowledge" to OpenAI to help the startup overcome the steep engineering hurdles associated with high-end hardware manufacturing.

The "Tip of the Iceberg": A Massive Talent Exodus

While Tan and Liu are the named defendants, Apple’s legal filings suggest a much larger problem. The company claims that more than 400 former Apple employees have joined OpenAI in recent years. This massive talent migration has created what Apple describes as a "porous border" through which confidential data has flowed.

The decision to send preservation letters to 40 additional former employees indicates that Apple’s internal investigators have identified a specific subset of the workforce that may have had access to particularly sensitive files or participated in encrypted communications regarding Apple’s intellectual property. Apple has stated in its filings that the evidence uncovered to date likely represents only the "tip of the iceberg," and it anticipates that the discovery process will reveal a broader conspiracy to strip-mine Apple’s engineering department.

Legal experts note that preservation letters are a standard but aggressive precursor to the discovery phase of litigation. By putting these individuals on formal notice, Apple is creating a legal "paper trail." If any of these employees delete messages or destroy documents after receiving the letter, they—and potentially OpenAI—could face severe sanctions for spoliation of evidence, which can include "adverse inference" instructions that allow a jury to assume the destroyed evidence was harmful to the defendant’s case.

OpenAI’s Defense and the Silicon Valley Culture

OpenAI has remained firm in its denial of the allegations. In a statement addressing the lawsuit, a spokesperson for the AI company stated that they are "not aware of any evidence that this complaint has merit." OpenAI characterizes the lawsuit as an attempt by a legacy tech giant to stifle competition and limit the mobility of high-tech workers.

The defense is expected to rely on the principle that employees have the right to move between companies and that "general knowledge and skill" acquired during a career cannot be claimed as a trade secret. OpenAI will likely argue that the innovations found in its hardware projects are the result of independent development and the unique intersection of AI software and hardware engineering, rather than the theft of Apple’s designs.

This legal battle touches on a long-standing tension in Silicon Valley: the balance between protecting corporate intellectual property and the region’s culture of rapid talent turnover and cross-pollination. California law generally favors employee mobility and prohibits non-compete agreements, which often leads companies like Apple to rely on trade secret litigation as their primary tool for preventing former employees from taking valuable knowledge to rivals.

A Timeline of Escalating Tensions

The friction between Apple and OpenAI has been building for several years, coinciding with the rise of generative AI.

• 2023: High-profile departures from Apple’s hardware division begin to accelerate, with Tang Tan’s exit in December marking a significant turning point.
• Early 2024: Reports emerge that OpenAI is collaborating with former Apple design chief Jony Ive and his firm, LoveFrom, to develop a new AI-centric hardware device, fueled by funding from SoftBank.
• June 2024: Apple announces "Apple Intelligence," its own suite of AI features, which includes a partnership to integrate OpenAI’s ChatGPT into iOS. This creates a complex dynamic where the companies are simultaneously partners in software and fierce rivals in hardware and AI development.
• July 10, 2026: Apple officially files a lawsuit against OpenAI in federal court, alleging trade secret misappropriation and breach of contract.
• July 17, 2026: News breaks that Apple has issued legal preservation letters to 40 former employees now at OpenAI, expanding the scope of the investigation.

Broader Implications for the AI Hardware Market

The outcome of this lawsuit could have profound implications for the future of the consumer electronics industry. Apple is seeking a permanent injunction that would prevent OpenAI from using any Apple-derived information in the development of its AI hardware. If granted, such an injunction could effectively halt OpenAI’s hardware projects, forcing the company to start from scratch or prove that its designs are entirely original.

Furthermore, the lawsuit serves as a warning to other startups and tech giants. As AI becomes the central feature of smartphones, wearables, and home devices, the "talent war" for hardware engineers who understand AI integration will only intensify. Apple’s aggressive stance suggests it will not hesitate to use its massive legal resources to protect its ecosystem.

The case also highlights the shifting landscape of Silicon Valley. For decades, Apple was the undisputed destination for the world’s top hardware talent. However, the allure of being at the forefront of the AI revolution has made companies like OpenAI formidable competitors for that same talent. This lawsuit is as much about controlling the narrative of innovation as it is about protecting specific technical designs.

Conclusion and Future Outlook

As the legal proceedings move toward the discovery phase, the industry will be watching closely to see what evidence Apple produces. To succeed, Apple must prove not only that its former employees possessed trade secrets, but that those secrets were actually misappropriated and used by OpenAI. This is often a difficult legal standard to meet, requiring specific proof of data transfers or identical technical implementations that could not have been achieved through independent means.

Regardless of the eventual verdict, the conflict underscores the high stakes of the AI hardware race. With Apple seeking significant damages and the return of all proprietary information, the legal battle is likely to be long and contentious. For now, the 40 former employees who received preservation letters find themselves at the center of a corporate war that could redefine the boundaries of intellectual property in the age of artificial intelligence.

In the broader context, this case adds to Apple’s growing list of legal challenges, including a major class-action lawsuit over iCloud pricing in the UK and a Supreme Court appeal regarding its App Store policies. However, the OpenAI lawsuit is unique in its focus on the very core of Apple’s identity: its hardware engineering excellence. By targeting former employees with these legal notices, Apple is making it clear that while it may partner with OpenAI on software, it will defend its hardware kingdom with every legal tool at its disposal.