Online travel company Expedia buying Orbitz Worldwide for about $1.33 billion

Expedia is buying rival online travel site Orbitz for approximately $1.33 billion. The deal comes less than a month after Expedia announced the $280 million acquisition of another rival, Travelocity.

Orbitz owns CheapTickets, HotelClub. Expedia owns Hotels.com and Hotwire.

Expedia, based in Bellevue, Washington, will pay $12 per share, a 25 percent premium to the Orbitz' closing price of $9.62 Wednesday.

The boards of both companies have approved the deal, but it still requires a nod from Orbitz shareholders.

Shares of Orbitz Worldwide Inc., based in Chicago, are up more than 23 percent in premarket trading and Expedia is up 5 percent.