Around $7 trillion of US options notional value rolls off the books Friday, accounting for around a quarter of the market, according to data from Citadel Securities.

The so-called 'triple witching,' where monthly S&P 500 Index options and single stock options all expire at the same time, is set to be the second-largest on record, according to the market maker.

The expiry, 60% of which takes place at the open, creates a "potential reset in the market's technical backdrop," wrote Citadel Securities' market intelligence team, led by Scott Rubner.

"As these positions expire or roll forward, the positioning that has helped dampen realized moves can change materially, potentially leaving the market more sensitive to underlying flows afterward."