NEW YORK ( TheStreet) -- Expedia ( EXPE - Get Report) was the star of Thursday's extended session after the Bellevue, Wash.-based online travel services provider disclosed plans to spin off its TripAdvisor business into a separate, publicly traded company.

Expedia said it expects the proposed transaction to be completed in the third quarter with existing shareholders receiving a yet to be determined proportionate distribution of stock in the TripAdvisor entity.

The stock was last quoted at $25.51, up 14%, on volume of roughly 3.1 million, according to Nasdaq.com. Based on a regular session close at $22.40, the shares were down 10% in the past year.

The remaining Expedia entity will include the company's domestic and international travel transaction brands, such as its namesake Web site, Hotels.com, and Hotwire.

TripAdvisor supplied revenue of $486 million in fiscal 2010, up 38% year-over-year. The company's total revenue was $3.35 billion for the year. Expedia is slated to report its fiscal first-quarter results on April 25, and the average estimate of analysts polled by Thomson Reuters is for a profit of $1.81 a share on revenue of $3.71 billion.

Tempur-Pedic

Shares of Tempur-Pedic ( TPX - Get Report) jumped after the mattress maker surprised Wall Street late Thursday with a better-than-consensus forecast for its fiscal first-quarter results and a higher profit outlook for the full year.

The Lexington, Ky.-based company said it sees earnings of 67 to 68 cents a share on sales of roughly $325 million for the March-ended quarter, well above the current average estimate of analysts polled by Thomson Reuters for a profit of 58 cents a share in the three-month period on sales of $289.1 million.

The stock was last quoted at $56.45, up nearly 11%, on volume of around 150,000, according to Nasdaq.com. Based on the regular session close at $50.99, the stock had appreciated nearly 68% in the past year, hitting a new 52-week high of $52.88 on Wednesday.

Seagate Technology

Disk drive maker Seagate Technology ( STX - Get Report) reinstated its dividend and gave an encouraging revenue outlook, and saw its stock surge.

The company said its board has approved a quarterly payout of 18 cents a share, payable on June 1 to shareholders of record on May 2. Seagate shelved a quarterly dividend of 12 cents a share in April 2010, so the new payout represents a 50% increase from prior levels.

At Thursday's regular session closing price of $14.69, the dividend implies a forward annual yield just shy of 5%. The stock advanced 7.7% to $15.82 in extended trades with volume running just above 900,000.

Prior to the after-hours move, the shares were down 21.7% in the past year, including a 30% drop since the start of 2011, although they'd seen a 49% bounce since hitting a 52-week low of $9.84 in late August.

Other stocks making notable moves in late trades include Hercules Offshore ( HERO), down 12% to $5.59 on volume of around 800,000 after shallow-water oil driller disclosed in a regulatory filing that its business practices are being investigated by both the Justice Department and the Securities and Exchange Commission; Idenix Pharmaceuticals ( IDIX), falling 12% to $2.85 on volume of around 60,000 after the Cambridge, Mass.-based drug developer unveiled plans to sell an undisclosed amount of additional stock in a public offering; and Sangamo Biosciences ( SGMO - Get Report), sliding 7% to $7.75 on volume of more than 40,000 after the Richmond, Calif.-based biotech said it's selling 6.7 million common shares.

-- Written by Michael Baron in New York.

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