(Bloomberg) -- Tesla Inc. escalated its trade secrets fight with Rivian Automotive Inc., accusing the maker of electric pickups of continuing to poach its employees and stealing “highly proprietary” battery technology.

The world’s leading electric-vehicle maker says the lawsuit it filed 14 months ago against Rivian hasn’t stopped the startup from raiding its staff and looting its intellectual property. That includes one instance this summer where Tesla defectors were “caught red-handed” stealing the core technology for its next-generation batteries, “the most essential element for any electric vehicle,” according to a court filing last month.

“Now apparently under pressure from investors after nearly a dozen years without producing a single commercial vehicle, Rivian has intensified its unlawful efforts,” Tesla said.

Rivian didn’t immediately respond to an email message seeking comment Sunday. 

The latest twist comes as Rivian is planning an initial public offering. The Irvine, California-based company is seeking a roughly $80 billion valuation, Bloomberg reported in August.

A California state court judge in San Jose allowed Tesla last week to add its new allegations to the pending case, along with three more of its former employees as defendants. Rivian had objected, arguing the claims are unsupported by the facts and that dramatically expanding the scope of the litigation will delay resolving it. Rivian already lost its initial request for dismissal of Tesla’s claims back in March.

Widening the Case

Superior Court Judge Peter Manoukian reasoned in a Sept. 28 ruling that it’s efficient to broaden the case at this juncture -- while making clear he’s not blessing the merits of Tesla’s claims.

“Here, defendants contend that Tesla has not alleged plausible facts to support its contention that defendants acquired confidential battery information,” he wrote. “That contention has some appeal to it.”

Rivian says Tesla dragged its feet since initially filing suit in July 2020 and hasn’t sufficiently specified the trade secrets it claimed were stolen, nor how the data at issue is distinct from what’s already public knowledge.

“For several of its trade secrets it has provided so little detail that Rivian is unable to ascertain what Tesla is claiming as its intellectual property, let alone whether what it is claiming is or could be secret,” Rivian said in a filing.

The case is Tesla Inc. v. Rivian Automotive Inc., 20CV368472, California Superior Court, Santa Clara County (San Jose).

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