Tesla Inc., its CEO Elon Musk and the U.S. Securities and Exchange Commission filed a joint filing Oct. 11 in support of their securities fraud settlement, saying the terms were in the "best interest of investors."

In September, Musk agreed to resign as chairman as part of the settlement of a lawsuit the SEC brought against him. The SEC accused Musk of misleading investors after he tweeted: "Am considering taking Tesla private at $420 a share. Funding secured." As part of the SEC settlement, Tesla and Musk also agreed to split $40 million in penalties.

However, in an Oct. 4 tweet, Musk mocked the SEC, calling it the "Shortseller Enrichment Commission." According to Reuters, Musk's tweet came shortly after U.S. District Judge Alison Nathan ordered Musk and the SEC to explain in a joint letter why their settlement, which let Musk remain as CEO, was fair and reasonable.