Some 55,900 in monthly Bitcoin options worth roughly US$2.1 billion will expire tonight and the bears appear to be in full control following last week’s crash.

Yesterday evening BTC was trading for US$38,300, after several moves to above US$40,000 this week have been rejected.

Bitcoin options

Opinions differ on just how much the expiry of monthly Bitcoin options influence the price. One Redditor performed a long analysis that found no influence, but other traders point to data suggesting the price of BTC dips towards the end of each month in the runup to the options expiry.

Clearly there are people out there who believe that the options play a role in Bitcoin’s price.

For the record, options on the dominant Deribit exchange expire at 6pm AEDT (8am UTC). There are also Bitcoin options trading on the Chicago Mercantile Exchange (CME) that expire at 1am AEDT (4pm, London time).