Microsoft has reminded the world of its claim that Linux violates 235 of its patents, by announcing a patent licensing deal with Casio Computer Co.

"Among other things, (the deal) will provide Casio's customers with patent coverage for their use of Linux in certain Casio devices," Microsoft says.

The terms of the deal were not announced, except that Casio will be paying Microsoft an undisclosed sum of money, Microsoft says.

The deal doesn't just cover Linux, but is a "broad, multiyear patent cross-licensing agreement," meaning Microsoft should also gain access to some of Casio's intellectual property.

Casio has been a longtime licensee of Windows and embedded Windows for its ruggedised computers and other devices. It also uses Linux and embedded Linux.

While Microsoft's focus lately has been to wrangle patent agreements out of Android, this news signals the company still hasn't given up on its claims on Linux. Microsoft has announced a handful of licensing deals involving Linux since 2007 including with Novell for SUSE (now owned by Attachmate), Linspire, Melco (the Japanese parent company of Buffalo), Fuji Xerox and Samsung.

Like Microsoft's other announcements concerning Linux patent-protection deals, this one doesn't make clear how much Casio is paying to cover its use of Linux versus how much it is paying for licenses of other technologies that may be included in the deal.

While on analyst once estimated that Microsoft is earning $5 per Android device sold by HTC, there have been no similar estimates as to how much Microsoft may be earning on its Linux licensing deals. 

Since Microsoft launched its IP licensing program in December 2003, the company has entered into more than 700 licensing agreements.