S&P Dow Jones Indices has revealed a series of constituent swaps for its S&P MidCap 400 and S&P SmallCap 600 benchmarks, a move that produced immediate price reactions in several named stocks during after-hours trading.
Amneal Pharmaceuticals (NASDAQ:AMRX) led the group of gainers, climbing 5.9% in after-hours trade. LegalZoom.com (NASDAQ:LZ) rose 5.2% and Dutch Bros (NYSE:BROS) advanced 2.9% after the index provider confirmed their upcoming inclusions.
Other companies named in the updates also saw modest moves. TTM Technologies (NASDAQ:TTMI), slated to move from the SmallCap 600 into the MidCap 400, ticked up 0.4%. American Healthcare REIT (NYSE:AHR) gained 2.9% on news of its entry into the MidCap 400, and Apellis Pharmaceuticals (NASDAQ:APLS) rose 2% as it prepares to join the SmallCap 600.
The index adjustments are largely a consequence of several pending acquisitions. SM Energy (NYSE:SM) is acquiring Civitas Resources (NYSE:CIVI), Rayonier (NYSE:RYN) is purchasing PotlatchDeltic (NASDAQ:PCH), Fifth Third Bancorp (NASDAQ:FITB) is in the process of acquiring Comerica (NYSE:CMA), and Huntington Bancshares (NASDAQ:HBAN) is buying Cadence Bank (NYSE:CADE). Separately, LegalZoom.com will replace Elme Communities (NYSE:ELME) in the SmallCap 600 after Elme announced ongoing liquidation activities.
S&P Dow Jones Indices said the first set of changes will take effect prior to the opening of trading on January 30, 2026. Under that schedule, TTM Technologies will replace Civitas Resources in the MidCap 400, and Amneal Pharmaceuticals will move into the SmallCap 600 by taking TTM's prior slot. The remaining reconstitutions are scheduled to be implemented before trading begins on February 2, 2026.
Market participants often watch index rebalances because additions or deletions can alter demand from index-tracking funds and institutional rebalancing flows. In this instance, the changes span several sectors including pharmaceuticals, legal services, consumer retail and regional banking, reflecting how M&A activity and corporate wind-downs can cascade into index composition adjustments.
Timeline of implementation
- January 30, 2026 (prior to market open) - TTM Technologies replaces Civitas Resources in the S&P MidCap 400; Amneal Pharmaceuticals takes TTM’s former position in the S&P SmallCap 600.
- February 2, 2026 (before trading begins) - Remaining announced changes will be implemented.
This reporting is limited to the changes and market reactions disclosed by S&P Dow Jones Indices and the price moves observed in after-hours trading; it does not include further market interpretation or projections beyond those details.