Bitcoin (BTC) and ether (ETH) kept trading within recent price ranges as the expiry of quarterly options and a strengthening dollar index failed to unsettle investors.

At 08:00 UTC, around 150,000 BTC options contracts, worth around $4.5 billion, and 1.2 million ether contracts, worth $2.3 billion, expired on Deribit, the world's leading crypto options exchange. Deribit controls over 85% of global crypto options activity.

The expiry was pivotal, considering market makers in BTC options were "long gamma" and could have added to spot price moves with their hedging activities. The largest cryptocurrency by market value, however, traded listlessly between $30,000 and $31,000 in days leading up to the settlement and remained locked in the narrow range afterward, recording just a 1% gain on the day to $30,700 as of 10:40 UTC, CoinDesk data show.