Taiwan prosecutors file new indictments in Tokyo Electron trade secrets case

By Wen-Yee Lee

TAIPEI, Jan 5 (Reuters) – Taiwanese prosecutors said on Monday they had filed additional indictments against the Taiwanese unit of Japan’s Tokyo Electron and three defendants in a case over the alleged theft of trade secrets from chipmaker TSMC.

The defendants include one previously indicted former TSMC employee surnamed Chen and two new suspects: another former TSMC employee also surnamed Chen and a former Tokyo Electron Taiwan employee surnamed Lu, the prosecutors said.

The prosecutors are seeking prison terms of seven years for the first Chen, eight years and eight months for the other Chen, and one year for Lu, they said.

SEEKING ADDITIONAL FINE

They are also seeking an additional fine of T$25 million for Tokyo Electron’s Taiwan unit on top of an initial request for a fine of up to T$120 million ($3.8 million) in December.

TSMC told Reuters that the prosecutors’ request for a supplementary indictment was based on findings from extended investigations related to the trade secret case for which the company took legal action in August 2025. “As the case is now under judicial proceedings, we are unable to provide further details at this time,” it added.

Chip equipment maker Tokyo Electron and its Taiwanese unit did not immediately respond to requests for comment. Reuters could not reach the former TSMC and Tokyo Electron employees for comment. 

Taiwanese prosecutors said last month they had charged Tokyo Electron’s Taiwanese unit with violating the National Security Act and the Trade Secrets Act after the first Chen was indicted in August for alleged theft of trade secrets from TSMC.

Prosecutors said they discovered during the investigation of the earlier case that the two Chens were suspected of illegally reproducing TSMC’s core trade secrets in violation of Taiwan’s National Security Act. Lu was suspected of destroying criminal evidence, prosecutors said.

Prosecutors said on Monday they had found that the unit’s cloud storage still contained TSMC trade secrets.

Tokyo Electron has said previously that it, as the parent entity, had not been indicted and the matter had no impact on its financial results.

($1 = 31.4530 Taiwan dollars)

(Reporting by Wen-Yee Lee. Editing by Christian Schmollinger and Mark Potter)