Reddit shares jump on S&P 500 entry; SUI joins MidCap 400

Seeking Alpha··US·Read original
2▲4 ▼2Impact / 5
Summary · why it matters

Reddit will replace AvalonBay Communities in the S&P 500 effective prior to the opening of trading on Tuesday, August 18, sending Reddit shares up about 13% in post-market trading on Wednesday. S&P 500 constituent Equity Residential is acquiring AvalonBay Communities in a deal expected to be completed soon, pending final conditions, and the combined company will be renamed Vivmark Residential and remain in the S&P 500. Additionally, Sun Communities will replace Webster Financial in the S&P MidCap 400 effective prior to the opening of trading on Thursday, August 20, as Banco Santander S.A. acquires Webster Financial in a deal expected to be completed soon pending final conditions.

Impact on assets 6

Real Estate± Mixed · 3 stocks
Sun Communities Inc
SUI
▲ PositiveCapitalrelevance

Joining the S&P MidCap 400 index, increasing exposure and passive inflows.

Equity Residential
EQR
▲ PositiveCapitalrelevance

Acquiring AvalonBay Communities, expanding portfolio and maintaining S&P 500 status.

Financials± Mixed · 2 stocks
Communication Services▲ · 1 stocks
Reddit, Inc.
RDDT
▲ PositiveCapitalrelevance

Joining the S&P 500 index, boosting visibility and passive fund demand.

© 2026 MarketIVNews