Ant Financial is now targeting a private round of financing for $3.5 billion

Alibaba Group Holding Ltd's finance affiliate is planning an initial public offering on Shanghai's main board in what could be China's highest IPO valuation since 2010, according to two people familiar with the matter.

Zhejiang Ant Small & Micro Financial Services Group Co has been profitable for three years, enabling it to meet the listing requirements, and may begin the process as soon as this year, the people said, requesting not to be named because the matter is private.