(FNSR) - Get Report

was falling more than 16% after the company was downgraded by J.P. Morgan due to valuation concerns.

The brokerage house lowered its rating on the high-speed communications systems maker to market perform from long-term buy. Morgan said it has concerns that profitability will continue to get pushed back as the company sees more aggressive pricing from its original equipment manufacturers.

Analysts polled by Thomson Financial/First Call are currently expecting the company to post break-even operating results in the fourth quarter of 2003.

While J.P. Morgan still expects Finisar to exceed its estimates for the fourth quarter of 2002, the firm said valuation is "a concern at these levels."

Shares of Finisar were falling about 67 cents to $3.39 on the news after closing at $4.06 Friday.