Oracle Corp. is buying hobbled Siebel Systems Inc. for about $5.85 billion, eliminating another competitor in its campaign to grab market share from business applications software leader SAP AG.

Under the terms of the deal announced Monday, Oracle will pay $10.66 per share in cash or stock for Siebel, whose products help manage companies’ relations with customers.

Despite four years of flagging fortunes, Siebel still has $2.24 billion in cash, reducing Oracle’s net takeover cost to $3.6 billion.