Foxconn Industrial Internet Co. Ltd. (FII) raised more than $4 billion in the biggest initial public offering in mainland China since 2015. A subsidiary of mega contract manufacturer Hon Hai Precision Industry Co. (TPE: 2354), more commonly known by its trading name, Foxconn Technology Group, FII produces electronic devices, industrial robots, and cloud service equipment.

In preparation for listing on the Shanghai Stock Exchange, the Shenzhen-based company reported in late May that it planned to offer up to 1.97 billion shares, at 13.77 yuan per share, in hopes of raising roughly $4.3 billion.

FII's IPO attracted the interest of some of China's largest Internet and technology companies, who moved quickly to secure stakes in the Foxconn subsidiary as cornerstone investors. In a May 27 filing with the Shanghai Stock Exchange, the company reported that Tencent Holdings Ltd. (HKG: 0700), Alibaba Group Holding Ltd. (BABA  ), and Baidu Inc. (BIDU  ) are each purchasing 21.8 million shares, or roughly a 3% stake combined, in FII.

The use of cornerstone investors is a new development in mainland China listings, but one that will likely be used more frequently as China draws tech giants to sell China Depositary Receipts in secondary IPOs to avoid flooding mainland markets.

FII hit the daily limit of 44% within mere seconds of trading, triggering a half-hour suspension. Government caps on IPO valuations and investor enthusiasm for new issues on mainland China helped propel FII to success. FII's market capitalization reached peaks of about 390.5 billion yuan, or $61 billion. This means that FII is now the biggest tech company listed in China, knocking Hangzhou Hikvision Digital Technology (SHE: 002415) to the number-two spot.

The IPO is part of Foxconn's plan to depend less on Apple (AAPL  ) for its smartphone manufacturing business and to explore new interests. "...Foxconn wants to reduce its customer concentration risk," noted James Wei, an analyst with Yuanta Investment Consultancy. Aside from Apple, FII counts Cisco (CSCO  ), Dell, Huawei (SHE: 002502), and Lenovo (HKG: 0992) amongst its clients.

The IPO also coincides with China's Ministry of Industry and Information Technology (MIIT) three-year plan to develop "smart manufacturing," as Beijing tries to integrate traditional manufacturing with digital technology. Rising hostilities between China and the US is pushing China to bolster its tech sector through capital markets.