Why Is MACOM Technology Solutions ( $MTSI ) Stock Down -10.98% Today? (Find out why any stock moved today on Tickeron.) MACOM Technology Solutions (MTSI) shares fell roughly 11% intraday, dropping from a prior close of $274.90 to about $244.72. The primary catalyst was a sector-wide semiconductor selloff triggered by calls from leading AI executives to slow the pace of frontier model development. Elevated oil prices, rising Treasury yields, and expectations of a hawkish Federal Reserve decision this week compounded the pressure on high-multiple chip stocks. $SITM $SMTC $KLAC $LRCX $VECO $AMKR $AMAT