EBay Inc. has agreed to buy GSI Commerce, a digital marketing and e-commerce company, for $2.4 billion.

Ebay, which runs its flagship online auction site along with PayPal, its online payments business, said Monday the acquisition will bolster its capacity to connect buyers and sellers around the world.

The online marketplace operator has agreed to pay $29.25 per share, a 51 percent premium to GSI's closing stock price on Friday. GSI shares surged 50 percent, or 9.73, to $29.11 in morning trading.

EBay has been working on improving its eBay.com website by doing things such as revamping its home page, cutting upfront listing fees it charges sellers and bolstering its search engine. CEO John Donahoe said in a statement that the GSI deal will enhance the company's position as "the leading strategic global commerce partner of choice for retailers and brands of all sizes."

As part of the deal, eBay plans to sell GSI's licensed sports merchandise business and 70 percent of shopping sites RueLaLa.com and ShopRunner.com.

EBay hopes to complete the deal in the third quarter. It says its 2011 net income per share will be 30 cents to 34 cents lower than its earlier outlook. In January, it had forecast earnings of $1.56 to $1.61 per share. Its adjusted earnings won't be affected. The company had forecast adjusted earnings of $1.90 to $1.95 per share in January.

The company expects the acquisition of GSI to add to its earnings per share in 2012.

Shares of eBay, which is based in San Jose, Calif., fell 73 cents, or 2.3 percent, to $30.97 in late morning trading.