A seemingly unstoppable advance fueled by Wall Street's obsession with all things AI took a breather on Friday, as the market faced the test of a massive options expiration.

The Nasdaq 100, which is heavy on technology, underperformed major benchmarks, led by losses in Microsoft and Apple , both of which had recently closed at all-time highs. Micron Technology ominous warning weighed on chipmakers, while Adobe rose on a bullish forecast. Despite snapping a six-day winning streak, the S&P 500 had its best week since March.

This week, stock traders caught between the fear of missing out on this year's rally and mounting concerns about an overbought market had to deal with something else: positioning.

With an estimated $4.2 trillion in options contracts tied to stocks and indexes set to mature, traders would typically be required to either roll over existing positions or open new ones. The impact of derivatives on trading was so significant this week that the market's favorite volatility gauge was climbing alongside the S&P 500 at one point.

The so-called VIX finally caved, wiping out this week's gains with Friday's drop.