Earlier this month, Didi Chuxing, the China-based ride-sharing company, closed yet another round of funding, to the tune of $5.5 billion. The company was a bit tight-lipped about the whole thing, but sources told CNBC that the latest funding round now brings Didi's valuation up to $50 billion.

That's quite an impressive jump from the $35 billion Didi was estimated to be worth back in August. This latest round had been rumored over the past several weeks, with SoftBank expected to head it up. Didi didn't officially say which companies were a part of the round, but the CNBC sources said Softbank, China Merchant Bank, Silver Lake, and others participated.

Picture of cars sitting in traffic.

Image source: Getty Images.

There's virtually no stopping this company

If you're having a hard time picturing just how big a $50 billion company is, just consider that Uber, one of Didi's frenemies, is currently worth $69 billion. The two companies fought it out in a battle royale of sorts in China until Didi paid $1 billion to take over Uber's business in the country. Didi gained a seat on Uber's board, and Uber received a 17% stake in Didi.

But the Uber purchase is now just a footnote in Didi's massive global expansion. The company has also invested $100 million Uber's other rival Lyft, is an investor in a Southeast Asia ride hailing company called Grab, invested in the Indian ride-hailing company Ola, and most recently invested in a Brazilian ride-hailing company, called 99, earlier this year.

After this latest funding round, Didi said in a statement that it will use the new funds "to support its global strategy and continued investments in AI-based technologies." That first part plays into the company's own global strategy that its president, Jean Liu, explained to Vanity Fair last year: "We're a big sponsor and big believer in local players. If there are no existing local players, we'll go there by ourselves. We will play a global game."

Didi is well on its way to building out its artificial intelligent technologies as well, and it opened a new AI and self-driving car lab in California back in March. As with many other tech companies these days, the company is looking ahead to the future $77 billion driverless car market. 

When will Didi go public?

Didi has already amassed some big-name investors, including Apple, but its global expansion and growing business isn't doing anything for individual investors just yet. There have been rumors that the company may go public some time this year, or perhaps as late as next year.

Less than a year ago, I wrote about Didi's possible future IPO, when the company was worth $28 billion. The current $50 billion valuation and new funding is sure to spur more talk of an IPO, but the last time Didi said anything about the idea, it was pretty emphatic that nothing was on the horizon. A company spokesperson told CNBC last year that, "We currently have no IPO plan, so there's no point of talking about location or schedule." For now, investors will have to watch Didi's growth from the sidelines.