While Pentair struggled, other market movers saw significant volatility following earnings and regulatory updates. Aehr Test Systems shares surged 27% to $91.56 after the bell, bolstered by a return to profitability in its fiscal fourth quarter.

Celcuity experienced a more complex trading session. Following FDA approval for its breast cancer treatment, Revtorpyk, the stock initially climbed 7% to close at $11.05. However, momentum reversed in after-hours trading, with shares falling 5.5% to $10.00. Meanwhile, Schmid Group saw its stock rise 11% to $5.02 after the company raised its full-year order intake guidance.