Shares of

QLogic

(QLGC)

fell sharply Monday after a downgrade by

U.S. Bancorp Piper Jaffray

analyst Ashok Kumar.

Shares of the Aliso Viejo, Calif., company recently tumbled $21.19, or about 30%, to $49.19 in morning

Nasdaq

trading. They closed at $70.38 on Friday's activity on the Nasdaq.

In his report, Kumar lowered the company's investment rating to neutral, citing "disappointing" third-quarter results. QLogic makes semiconductors and interfaces for network storage systems. Kumar, who also slashed his rating on

Emulex

(EMLX)

, said QLogic's stock faces a valuation compression and earnings risk. Emulex stock

plunged Monday after it warned of lower third-quarter results.

Kumar also said his downgrades were influenced by the "ailing" storage industry, marked by the "disappointing performance" from

Network Appliance

(NTAP) - Get Report

. Network Appliance

reported third-quarter earnings on Feb. 8.