Siliconware Precision Industries (SPIL) has disclosed plans to form a joint investment business with three other Taiwan-based chipmakers. The joint investment entity will mainly invest in semiconductor companies listed on the Taiwan Stock Exchange (TSE), said the IC backend service company.

IC foundry United Microelectronics (UMC), and backend houses King Yuan Electronics Company (KYEC) and Sigurd Microelectronics will all participate in the formation of the joint investment business, according to respective company filings with the TSE.

SPIL announced that the company through its corporate ventures arm will take over 48 million shares of the joint investment entity for a 30.4% stake, at NT$50 (US$1.54) per share.

UMC will buy 60 million shares of the joint investment company for a total of NT$3 billion. KYEC will invest a maximum NT$1 billion in the new investment entity, while Sigurd will spend NT$500 million to acquire shares of the company.

According to market sources, there will be another Taiwan-based chipmaker subscribing to shares of the joint investment company for NT$1 billion. The new entity will be established later this month (November 2015) with an initial capital of around NT$7.9 billion, said the sources.

Rumors have started to circulate that the formation of the joint investment firm initiated by SPIL could be aimed to dilute Advanced Semiconductor Engineering's (ASE) holding in SPIL.

ASE in September 2015 purchased 25% shares of SPIL and became the largest shareholder of the fellow packaging and testing company, while SPIL argued ASE's stake investment is a hostile takeover.