Volkswagen’s April Fool’s Day joke is now being investigated by the SEC, according to The Verge. Volkswagen’s American arm created a fake rebranding, known as “Voltswagen,” which was publicized in a draft of a press release that was supposedly “accidentally” published, according to Der Spiegel.

In the press release, the company changed the name in order to boost its line of electric vehicles. The press release also contained quotes from Volkswagen of America CEO Scott Keogh verifying the name change.

Volkswagen issued an official press release around a day later in an attempt to clear up the matter. However, reporters, including some at the Associated Press, said officials at Volkswagen of America had insisted the name change was true.

Now, the SEC wants to know whether the company broke any security laws and find out whether it impacted Volkswagen’s stocks. The company stocks rose as much as 12.5 percent during that time.

That stock price adds up to billions of dollars of market value. While publicly traded companies are not supposed to fool their shareholders even if it is a joke, many experts doubt that Volkswagen will actually receive an official penalty if the SEC finds them guilty of wrongdoing, according to The New York Times.

It is not the first time the SEC has recently found fault with an automaker. The SEC filed a lawsuit last year against Tesla CEO Elon Musk for alleged securities fraud after he tweeted “Funding Secured” last August.