The all-cash offer of $65 per share amounts to a 44% premium over Sybase's three-month average stock price, according to SAP. Sybase's board has voted unanimously in favor of the deal, which requires clearance by antitrust officials, SAP said.

The pending deal would significantly expand the technological portfolio of SAP, which is known most of all for its ERP (enterprise resource planning) applications.

"They're investing in two areas they think will be important for them," namely mobile technology and in-memory databases, both areas where Sybase is strong, said Ray Wang, partner with Altimeter Group.

In-memory processing is a particular interest of SAP co-founder and chairman Hasso Plattner, who has predicted it will reshape the enterprise application arena thanks to the performance improvement it can provide over databases that must read from and write to disks.

In a statement, SAP said its own in-memory technology would boost the capabilities of Sybase's database platform.