Oracle chief executive Larry Ellison has stopped his long-time rival Marc Benioff, chief executive of Saleforce, from giving a planned keynote address at the OpenWorld customer event in San Francisco.
Benioff was due to deliver the keynote on Wednesday at 10.15am, and was to be joined by Dell chairman and chief executive Michael Dell.
However, Benioff announced on Twitter that his invitation had been withdrawn for no apparent reason.
"I don't know why. Larry just cancelled my keynote tomorrow! I'm disappointed too!" he wrote.
Benioff said that he will instead host a talk about the recent social updates to Salesforce's cloud applications at the nearby Ame Restaurant in the St Regis Hotel at 10.30am.
Oracle told V3, though, that there was nothing underhand about the move, explaining that it was a simple scheduling matter.
"Due to the overwhelming attendance at Oracle OpenWorld we had to make several session changes. The Salesforce.com Executive Solution Session was moved to Thursday at 8:00am in the Novellus Theatre," the firm said.
Despite this, it is generally thought that Ellison fears he may be upstaged by his rival. Benioff told attendees last year at OpenWorld to beware of the "false cloud".
Ellison hit out at Salesforce during the 2010 event, particularly criticising the firm's security model, while Benioff's return keynote was peaceful in response, earning him a mark of respect.
Ellison's keynote addresses this year have also been criticised for being dull. During the opening slot, Ellison drilled down into very technical detail on the Exa-line products, which some attendees found uninspiring.
Meanwhile, analysts attending the event have critcised Ellison's keynote on Twitter and it can't have helped that both messages were re-tweeted by Benioff.
"How do you tell your founder [and] CEO that his keynote sucks. Oracle marketing has a tough job," said Constellation Research analyst Ray Wang.
"What we saw today from Larry Ellison was abysmal. And shows why Salesforce under Benioff has captured the zeitgeist," said Diversity Analysis analyst Ben Kepes.
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