Pinduoduo founder and CEO Colin Huang has surpassed Alibaba founder Jack Ma to become the second-richest man in China, according the real-time billionaire list compiled by Forbes.

Why it matters: Pinduoduo’s 40-year-old founder, also known as Huang Zheng, saw his net worth rocket in June, triggered by robust sales growth during the annual June 18 shopping promotion known as 618.

Details: Huang, an ex-Googler, is now China’s second-richest man with a net worth of $45.4 billion, second only to Tencent’s Ma Huateng whose net worth is $52.6 billion. Huang holds a 45% stake in social e-commerce platform, Pinduoduo. Jack Ma, who retired last fall from the daily operations of Alibaba to focus on philanthropy, saw his net worth fall to $43.9 billion from $45 billion as of 5 p.m. the previous trading day.

Pinduoduo didn’t reveal sales figures during the period, saying only that sales of milk formula increased 510% year on year during the period.

“Pinduoduo users don’t need to wait twice a year to get the best value for their money because they get the best value on our platform every single day,” the company said in a statement.

Shares of Nasdaq-listed Pinduoduo have more than doubled in value since the beginning of the year, boosting the e-commerce company’s market cap from $44 billion on Dec. 31, 2019, to $104.89 billion as of Monday.