SharkNinja shares rose 5% after‑hours as S&P Dow Jones announced its S&P MidCap 400 inclusion effective May 18, 2026.
Flowers Foods rose 1.4% after‑hours on its move to the S&P SmallCap 600, replacing CSG Systems, now being acquired by NEC.
F&G Annuities & Life rose 3% after‑hours on S&P SmallCap 600 addition, replacing Mister Car Wash, now being bought by Leonard Green.
Index inclusions typically trigger buying from funds that track the benchmarks, supporting further price gains.