TAIPEI (Taiwan News) — Prosecutors questioned a manager at lens manufacturer Largan Precision on Friday amid an investigation into securities fraud.

Taichung prosecutors said they were investigating suspected insider trading by employees of Largan and other firms. They said the Taipei prosecutors also investigated the case in September, per UDN.

Taichung prosecutors said investigators searched 15 locations in Taichung and Taipei on Thursday and took nine suspects and one witness in for questioning. A Largan manager surnamed Yao (姚) posted bail of NT$500,000 (US$15,360) on Friday after being questioned overnight.

Three other people not employed by the company were also questioned and released on bail of between NT$150,000 and 500,000. Largan issued a statement that said the investigation was unrelated to it and would not affect business.

Largan Precision manufactures lenses for smartphones and other applications and is a supplier to Apple. The publicly listed company reported NT$59.46 billion in revenue last year.