The US Securities and Exchange Commission has opened an inquiry into the US unit of Volkswagen's AG over a marketing stunt in which it falsely said it was changing its name in the US to 'Voltswagen', a person briefed on the matter confirmed.
Spiegel first reported the inquiry and the SEC's request for information about the issue made in early April and quoted VW as confirming the investigation.
Volkswagen declined to comment on the matter to Reuters. The SEC did not respond to a request for comment.
The company in March apologised after a false statement it issued about a phony name change was widely slammed on social media.
The stunt came just ahead of April Fool's Day when companies often release prank statements and was meant to call attention to its electric vehicle efforts, the carmaker said.
The initial statement outlining the name change, posted on its website and accompanied by tweets, was reported by Reuters and other outlets globally and included a detailed description of its purported rebranding efforts and new logos.
At least one analyst wrote a research note praising the name change. VW's preferred shares, common shares and ADRs rose on the day of the phony name announcement.
Volkswagen Group of America CEO Scott Keogh told Reuters in an April 1 interview that the phony name announcement was a "gag" and an attempt to "have some humour and "to celebrate our profound focus on electrification".
Volkswagen in 2015 admitted to using illegal software to rig diesel engine tests in the US, sparking Germany's biggest corporate crisis and costing the carmaker more than 32 billion euros in fines, refits and legal costs.