← All S&P SmallCap 600 additions
ACMR — S&P 600 index addition
ACM Research
Sector
Unknown
Announced
Sep 26, 2025
Effective
Sep 26, 2025
Replaced
WK Kellogg Co
1W after inclusion
+10.0%
+9.7% vs S&P 600
1M after inclusion
+10.5%
+10.9% vs S&P 600
3M after inclusion
+6.2%
+3.8% vs S&P 600
6M after inclusion
+20.8%
+14.0% vs S&P 600
1Y after inclusion
—
window not elapsed
Indexed performance around the effective date (effective close = 100)
Prices last updated: 2026-09-16 06:30 UTC (9h ago)
Run-up in the 30 days into inclusion: +32.2%
Other stocks added to the S&P SmallCap 600
- ADIG — ADI Global Distribution joined on Aug 4, 2026.
- FIVN — Five9 joined on Aug 3, 2026.
- VVX — V2X, Inc. joined on Jul 27, 2026.
- TPC — Tutor Perini joined on Jul 24, 2026.
- ROAD — Construction Partners joined on Jul 22, 2026.
- KRMN — Karman Holdings joined on Jul 17, 2026.
See the full S&P SmallCap 600 additions log or the index review calendar.