Elon Musk purchased about $1 billion shares of Tesla, his first stock buyback in the company in five years. The announcement caused Tesla’s share price to jump about 7% in a day where there was no other public news to explain the surge.

At the same time, a number of unusually aggressive short-term call options were being traded despite there being no expected catalyst such as earnings or major announcements. Some traders might have had advance knowledge of Musk’s purchase, implying the moves could be more than just speculation.