(Bloomberg) — President Donald Trump is blocking HieFo Corp. from acquiring semiconductor-related assets from Emcore Corp., citing national security reasons.

The order, released Friday, notes that HieFo, a Delaware-based company, was organized and is controlled by a Chinese citizen and targets the firm’s acquisition of “assets comprising the digital chips and related wafer design, fabrication, and processing businesses of” Emcore.

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The companies in 2024 announced that they had completed a deal to sell New Jersey-based Emcore’s chips business and indium phosphide wafer fabrication operations for $2.92 million.

Trump’s order says that deal “threatens to impair the national security of the United States,” the latest move by the administration aimed at cracking down on Chinese access to advanced semiconductor technologies.

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It directs HieFo to divest within 180 days unless the Committee on Foreign Investment in the United States, a secretive federal government panel that reviews deals involving American companies on national security grounds, grants them additional time.

“Cfius identified a national security risk arising from the transaction relating to potential access to Emcore’s intellectual property, proprietary know-how, and expertise and to the potential diversion of supply of indium phosphide chips manufactured by the Emcore Digital Chips Business away from the United States,” the Treasury Department said in a statement.

–With assistance from Derek Wallbank and John Harney.

(Updates with Treasury Department comment, in sixth paragraph.)

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