What happened

Shares of Chinese electric-vehicle maker NIO (NIO 1.48%) were moving higher on Friday, after data showed that it beat Tesla (TSLA 1.26%) on one key sales metric in China in April. 

As of 11 a.m. EDT today, NIO's American depositary shares were up about 6.9% from Thursday's closing price.

So what

NIO was the best-selling brand in China's fast-growing all-electric SUV market in April, according to new data from the China Automotive Technology and Research Center. While Tesla's Model Y was the best-selling electric SUV in China in April, with 5,520 units sold, NIO's three electric SUV models sold a combined 7,404, enough for a 23% share of the market.

A red NIO ES6, an upscale mid-sized electric SUV.

While no single NIO outsold Tesla's Model Y in April, combined sales of the similarly sized ES6 (shown) and closely related EC6 were 5,786, topping the Model Y's 5,520. Image source: NIO.

Of course, that data comes with an asterisk (or at least an excuse): The Model Y production line at Tesla's Shanghai factory was reportedly shut down for about two weeks in April, so supplies might have been tight.

That said, demand might also have been a factor. Tesla's China sales fell by about 67% in April from March, as CEO Elon Musk's feud with the Chinese government in the wake of a series of accidents and protests sent many potential buyers to other brands. 

Now what

Auto investors who are inclined to dismiss the Tesla data should note that while Tesla managed to move 25,845 Shanghai-built vehicles in April, more than half of those (14,714) were exported. 

Clearly, the level of Chinese demand for Teslas is in question right now. That's bad news for the Silicon Valley carmaker's ambitious growth plans, but it seems to be giving NIO a nice opportunity to gain market share.