(MONEY Magazine) – Once again, the tech stocks in the MONEY 30 were seriously slammed by Wall Street. Indeed, three companies--Cisco, Oracle and Sun Microsystems--each lost more than 25% of their value in the month ending Feb. 16.

In early February, networking giant Cisco missed analyst targets for fiscal second-quarter results. The company also warned that revenues probably wouldn't be growing in the next six months. It was the first time in almost four years that Cisco had failed to meet expectations--and the bellwether for the Internet economy was promptly gonged by the Street. Other major tech stocks, including Oracle and Sun, fell after analysts lowered their earnings estimates.

The top gainer in the MONEY 30 mix was Amgen, which zoomed nearly 13% on Jan. 22 after a federal judge ruled in the biotech company's favor in a patent dispute with a major competitor. The ruling essentially preserves Amgen's monopoly for its top-selling Epogen drug, which treats anemia by boosting red-blood-cell production.

--ERICA GARCIA