Oracle has reached a "definitive agreement" to acquire BEA Systems for approximately $8.5bn.

The board of directors of BEA Systems has unanimously approved the transaction, according to Oracle.

The deal is anticipated to close by the middle of 2008, subject to BEA stockholder approval, regulatory approvals and customary closing conditions.

"Over the past several months our board of directors, with the assistance of independent financial and legal advisors, has reviewed various ways to maximise stockholder value, including discussions with third parties about a possible sale of the company," said BEA chairman and chief executive Alfred Chuang.

"This transaction is the culmination of that diligent and thoughtful process, and we believe it is in the best interests of our shareholders."

Safra Catz, president and chief financial officer at Oracle, added: "We expect this deal to be accretive to Oracle's earnings by at least one to two cents on a non-GAAP basis in its first full year after closing."

Oracle chief executive Larry Ellison said: "The addition of BEA products and technology will significantly enhance and extend Oracle's Fusion middleware software suite."