Bitcoin has been on a huge run, nearly doubling its all-time high in recent weeks to $40,000 per BTC. Of course, this action has sparked plenty of unusual options activity in blockchain related stocks like Riot Blockchain (RIOT). Over 400,000 options traded in RIOT on a big up day for BTC last week. About 70% of the action was in calls, which tends to be bullish for the stock. Some of the bigger trades may have been tied to a weekly covered call strategy meant to generate robust yields from owning RIOT shares and selling calls.