For years, scientists worked on an esoteric piece of technology that they hoped could help the U.S. break China’s grip on the global supply of rare earths, a type of mineral essential to making everything from jet fighters to cars.
That technology and a scientist involved in its development are now the subject of a bitter lawsuit between two companies racing to become the dominant supplier of U.S.-made rare earths.
The fight is emblematic of the cutthroat competition to establish an all-American supply chain for rare earths. The urgency emerged last year, when China—which controls some 90% of the world’s rare-earth magnet supplies—cut them off amid a trade fight with the U.S. Car factories ground to a halt, and defense manufacturers scoured the world for hidden stashes.
In response, the U.S. government and private investors have poured billions into companies such as USA Rare Earth and MP Materials to build a complete supply chain, stretching from the mines to the finished rare-earth magnets that power motors and guide missiles.
The huge sums flooding into the sector are fueling a talent war as newly flush companies seek to lock up America’s scarce rare-earth technicians.
In the case of the technology at the center of the lawsuit, scientists at MP Materials, America’s biggest rare-earth miner, worked for years out of a small industrial space dubbed “The Garage”—also known as “Bobcat”—to develop the technique, known as grain boundary diffusion. Now the company alleges that a former engineer took its valuable formula to USA Rare Earth.
USA Rare Earth, which like MP Materials has received large-scale government support to build a complete rare-earths supply chain, denies that it stole trade secrets. “We believe this lawsuit amounts to nothing more than an attempt by MP to slow USAR’s bold vision and significant momentum,” the company said, referring to itself by its Nasdaq ticker symbol.
MP Materials says USA Rare Earth embarked on a “raiding mission,” hiring at least eight key MP employees who were valuable “primarily because of information they received from MP Materials, not pre-existing expertise.”
One of these employees, Kevin Elkins, a material science and engineering Ph.D., worked for MP Materials for 2½ years from 2022 to 2024, including as a senior engineer involved in the company’s magnetics division. The next year he joined USA Rare Earth’s magnetics operations as an associate director and was promoted to director, according to his LinkedIn profile. MP alleges that he took with him sensitive technology related to grain boundary diffusion and is seeking at least $5 million in damages. Elkins denies the allegations.
Grain boundary diffusion involves applying tiny quantities of the most expensive and elusive rare earths, known as heavy rare earths, to a magnet to make it heat-resistant without sacrificing magnetic strength. James Litinsky, MP’s chief executive, has described the company’s yearslong effort to develop such technologies as “sort of a private-market Manhattan Project.” MP says it wanted to keep it so secret that it wasn’t patented, to avoid any public disclosures about the technique.
During a meeting an MP executive had with an industrial machinery company involved in magnet making, the machine maker briefed the MP executive on a grain-boundary-diffusion technique that precisely matched MP’s own, down to specific formula components.
The machine maker told MP it had worked with an Oklahoma-based magnet maker on the technique. Since USA Rare Earth is based in Stillwater, Okla., MP believes it demonstrates that USA Rare Earth, as well as Elkins, had come into possession of MP’s grain-boundary-diffusion technology.
USA Rare Earth dismissed the charges in a rebuttal it filed in Texas court last week, saying the technology is “readily ascertainable via independent development, reverse engineering, and/or other proper means.”
“Competition is good but blatant theft is unacceptable,” said an MP spokesman.
A spokeswoman for USA Rare Earth described MP’s claims as “baseless.”
“Having the two leading U.S. names in dispute risks distracting the sector at the moment Washington says it wants a domestic industry built,” said David Abraham, who runs Materium Strata, a critical-mineral advisory. MP and USA Rare Earth were among the U.S. companies targeted by new Chinese export restrictions announced last week.
MP, which operates one of the world’s largest rare-earth mines in California, has been receiving government funding for years. It struck a multibillion-dollar deal with the Pentagon last year on the heels of China’s move to restrict rare-earth-magnet exports.
In the lawsuit, MP says that it spent a decade investing billions in developing technical capabilities from scratch, whereas “USA Rare Earth lacked the people and the technology to fulfil its public commitments.” Further, “USA Rare Earth has a well-established pattern of announcing and then failing to achieve its plans,” MP said, calling the company a “want-to-be competitor.”
A spokesman for USA Rare Earth says the company is “making significant strides in furthering America’s strategic interests.”
USA Rare Earth, which announced $1.6 billion in federal backing in January, is bringing online a large magnet facility in Stillwater. Production at a prospective mine in Texas is expected in 2028. It has used its war chest to announce acquisitions of Less Common Metals, a U.K.-based rare-earth-metal maker, and Serra Verde, which owns the Pela Ema mine in Brazil that produces highly coveted heavy rare earths.
Write to Jon Emont at jonathan.emont@wsj.com
