San Francisco ? Oracle Corp. increased its offer Wednesday for rival PeopleSoft Inc. by nearly 22 percent to about $6.3 billion, an aggressive effort to push investors to approve a deal that PeopleSoft executives have tried to thwart.

Oracle’s sweetened offer is the latest salvo in increasingly bitter competition in the business software niche.

Germany’s SAP AG dominates the market, followed by Oracle, PeopleSoft and about 3,000 smaller vendors.

Oracle chief financial officer Jeff Henley said management decided to increase its cash offer to $19.50 a share from $16 a share after meetings this week with PeopleSoft’s largest shareholders.

“We’ve received input from a broad range of investors,” Henley said. “Our revised price represents a great value for PeopleSoft shareholders.”

Oracle’s new offer represents a 13.7 percent premium on PeopleSoft’s closing share price Tuesday. Oracle’s original offer represented a premium of about 6 percent.

Shares in PeopleSoft rose 78 cents Wednesday, or 4.5 percent, to close at $17.93. Oracle shares rose 7 cents to close at $13.42. Each are traded on the Nasdaq Stock Market.

PeopleSoft issued a statement saying its board of directors would discuss the new offer and make a recommendation “in due course,” but urged shareholders to “take no action at this time.”

“The board concluded that the original offer dramatically undervalues the company based on its financial performance, continued market leadership and significant future opportunities,” the statement read.