Wise Road Capital is exploring a potential sale of ATX Semiconductor, a China-based outsourced semiconductor assembly and testing (OSAT) business it acquired from Taiwan’s ASE Technology in 2021, according to four sources familiar with the matter.

Citi has been mandated to advise on the sale, two of the sources said.

The sale process remains at an early stage, with Wise Road sounding out potential buyers for the business, including Chinese strategics, the other two sources noted.

The private equity firm is seeking a valuation no lower than its original acquisition price, one of them mentioned.

Wise Road acquired four OSAT facilities in Shanghai, Suzhou, Kunshan and Weihai from ASE Technology in December 2021, in a transaction with an announced enterprise value of approximately USD 1.46bn.

ASE subsequently acquired a 16.48% stake in Hong Kong United Ascend Holdings, an investment vehicle with interests in ATX, for USD 380m in September 2024.

ATX now operates five manufacturing facilities, comprising four in China across Shanghai, Suzhou, Kunshan, and Weihai, and one in Melaka, Malaysia, per its website. The company provides semiconductor packaging, wafer testing and final testing services across the automotive, consumer electronics, communications and industrial sectors.

It is also expanding capacity through a packaging and testing project in Kunshan announced in May 2026, which is expected to have an annual production capacity of 7.5 billion chips once fully operational.

The potential sale comes amid dealmaking activity involving other OSAT assets in China and the broader APAC region. Arizona, US-based Amkor Technology is exploring options including a stake sale in its China operations, which could value the business at USD 1bn–USD 1.5bn, Bloomberg reported in August 2026. Separately, Wise Road has kicked off the sale process of Singapore-headquartered OSAT business UTAC Holdings, which could fetch around USD 3bn, Mergermarket reported in May 2025.

Citi declined to comment on the matter. Wise Road, and ATX did not return requests to comment.