Chinese e-commerce giant Alibaba plans to invest $200 million in Snapchat at $15 billion valuation, sources tell Bloomberg.

This funding would be in addition to, not part of, the $500 million funding round Snapchat was reportedly in talks about last month, sources tell Bloomberg's Serena Saitto. That round had Snapchat valued at $19 billion, instead of $15 billion.

This isn't the first time Alibaba's name has come up in funding talks. Saitto reported that the two companies were in discussions about a round at a $10 billion valuation back in July.   

The company ended up raising $468 million in December--at a reported valuation of between $10 and $20 billion--bringing its total funding to $649 million (there were 23 un-named investors in that round, and TechCrunch reported at the time that Yahoo invested, but Alibaba didn't). 

In the past year, Snapchat has made some major moves to transform its image from that of a "sexting" app, to a content platform, especially with the rollout of its "Stories" feature, and its media channel Discover, which lets a few major news sites publish content and videos. Through Discover, Snapchat will keep about 40 percent of any ad revenue it sells for publishers.  

A $15 billion valuation would make Snapchat the third-most valuable venture-backed company in the world, tied with Palantir but after Xiaomi and Uber (with values of $15 billion, $45 billion and $40 billion, accordingly). 

--This story first appeared on Business Insider.