The S&P 500 is edging toward the 6,400 mark after closing at 6,365 on Wednesday, a level that traders identify as heavy with same-day call-option interest and potential technical resistance. Further call walls sit near 6,500, while put support is clustered around 6,300, according to market-making data. Options metrics point to a moderation in bullish conviction. An internal ‘option score’ that tracks liquidity and positioning has slipped from the 4–5 range to about 3 as the index approaches the key strike. The gamma-flip level—where dealer hedging may amplify moves—stands at 6,345, suggesting the market could become more volatile if spot prices fall below that threshold. Across broader U.S. equity derivatives, implied volatility remains subdued. On the Nasdaq-100, implied volatility of 15.7% still exceeds its 9.3% realized level, yet an IV rank of 5.3% signals premiums remain cheap relative to the past year. The put-to-call open-interest ratio of 1.09 indicates traders retain a slightly defensive tilt even as benchmark indexes sit near record highs.