Elon Musk delayed filing a form and made $156 million

Elon Musk was 11 days late in publicly declaring he had amassed a large stake in Twitter. That omission may have earned him $156 million, according to a half-dozen legal and securities experts.

That’s because of a 50-year-old law that requires that investors notify the Securities and Exchange Commission when they surpass a 5 percent stake in a company. Musk reached that benchmark March 14, according to the filings. But he made his public disclosure only Monday.