Twitter Inc and its advisers were not sure at first how seriously to take him.

Elon Musk's US$54.20 (RM236)-per-share offer price for the social media company on April 14 contained the digits 420, a reference to a trope for smoking marijuana. Financing documents he submitted last week in support of his bid were signed on April 20, abbreviated as 4/20.

Such references harken back to his...