Twilio’s Post-Index Addition Slide: 288th in U.S. Volume Amid S&P MidCap 400 Shake-Up

Twilio (TWLO) closed at a 0.86% decline on Aug. 14, 2025, with a trading volume of $0.36 billion—down 45.3% from the prior day—ranking 288th among active U.S. equities. The stock’s inclusion in the S&P MidCap 400 index, effective Aug. 19, marked a key development as it replaces Amedisys Inc. in the benchmark. The index addition, part of a broader reconstitution, reflects Twilio’s growing market relevance in the information technology sector.

The index change follows UnitedHealth Group’s acquisition of Amedisys, which triggered the reshuffling. While the move typically boosts visibility and liquidity for constituent stocks, Twilio’s immediate post-announcement performance remained subdued. Investors may weigh the long-term implications of enhanced index exposure against short-term volatility.

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