This works out at US$9.50 per share.
The sale tops the IBM offer to buy Sun for US$9.40 per share, which fell through earlier this month when Big Blue withdrew its bid.
Oracle said it expects the purchase to generate more profit than the previous acquisitions of BEA, PeopleSoft and Siebel combined, forecasting the acquired business to contribute over US$1.5 billion to its non-GAAP operating profit in the first year, and more than US$2 billion in its second year.
"The acquisition of Sun transforms the IT industry, combining best-in-class enterprise software and mission-critical computing systems," said Oracle chief executive Larry Ellison.
"Oracle will be the only company that can engineer an integrated system - applications to disk - where all the pieces fit and work together so customers do not have to do it themselves.
"Our customers benefit as their systems integration costs go down while system performance, reliability and security go up."
Oracle said that Sun’s Java software is the most important software Oracle has acquired. Oracle uses the software to build its Fusion Middleware.
