Emulex Corp said on Thursday that its board had unanimously rejected Broadcom Corp's sweetened $912-million buyout offer, saying that it significantly undervalues the company's long-term prospects.

Shares in the storage technology company fell 14 percent in premarket trading.

Last week, Broadcom raised its cash bid to $11 a share from $9.25 per share and dropped its hostile consent solicitation and a lawsuit against Emulex, in what it called a final effort to buy Emulex.

Emulex said its board rejected the bid after a thorough review carried out with the assistance of its financial advisors.

It also raised its estimate for its fiscal fourth quarter that ended June 28 and said won two new design contracts in recent weeks, which it said validates its earnings and revenue projections for 2012.

Emulex expects fourth quarter revenue of $78 million to $79 million, compared to its target range of $73 million to $80 million issued in April 2009 during its third quarter conference call.

It also expects fourth quarter earnings at the high end of the prior forecast of 1 cent to 5 cents per share, excluding costs related to the Broadcom takeover effort and other items.

(Reporting by Sinead Carew; Editing by Derek Caney)