Yahoo just running Oracle Linux on a few database servers.
Red Hat has declared itself unimpressed with Oracle's list of 26 customers for its Red Hat Linux support business.
In a Q&A session with financial analysts on Thursday, Red Hat chief executive Matthew Szulik said that Oracle's high profile win of Yahoo's business is in fact limited to a few Oracle database servers.
"I spoke with Yahoo executives yesterday, and they were very quick to respond that they have had, and continue to have, a very successful relationship with Red Hat," said Szulik.
"They have selected Oracle Linux to run on a number of Oracle database servers, but expect currently, and in the future, to have a successful relationship with Red Hat."
Oracle published a list of 26 companies last week which it claimed had signed up for Oracle's Linux support offering. The service is seen as a competitive threat for Red Hat because it promises a virtually effortless migration between the two.
Although identical to Red Hat Enterprise Linux, Oracle's software is generally referred to as Oracle Enterprise Linux.
Oracle's press release touting the customer wins was conspicuously short on details about the company's new clients, mentioning only one instance in which a company had migrated away from Red Hat's software.
This leaves the possibility that the other companies are new Linux users, or traded in some other operating system or Linux distribution.
The case of Yahoo's defection had already been reported. But the scope of Yahoo's switch is not limited to the internet portal and Red Hat is also "in discussions about expanding the Red Hat Enterprise Linux footprint", according to Szulik.
Szulik also dismissed claims that Novell's interoperability agreement with Microsoft gives its SuSE Linux distribution a competitive edge over Red Hat.
As previously reported, the open source company is in talks with Microsoft on improving interoperability.
"It probably just doesn't get the public fanfare that you read online," explained Szulik. "We will continue to work with all vendors, whether Microsoft or anyone in the client or server side, to fulfil the goal of interoperability."
Szulik commented on the Oracle competition as part of Red Hat's annual earnings release. Net income fell 25 per cent to $73.4m year over year, while revenue increased by 44 per cent to $491m.