The producers of the Samba open source file and print server software said last week that patents held by Microsoft do not affect its software. Samba author Andrew Tridgell said, "Samba is completely unaffected by these patents."

Fears that Microsoft might charge US uses of the Samba software for patent infringements were raised after Microsoft issued its "royalty-free CIFS technical reference licence agreement" in March. This agreement governs the use of Microsoft documentation covering the CIFS protocol and related patents. The terms are royalty-free provided licensees are not offering their products using an open-source licence such as the General Public Licence (GPL).

Following the publication of this agreement, many Samba users were left wondering if they might have to pay royalties to Microsoft or stop using Samba altogether. Development of Samba itself also appeared threatened.

Lawyers said European firms would not be directly affected by any patents held in the US by Microsoft, but there was concern that if the patents affected Samba in the US, they would have a knock-on effect throughout Europe and the rest of the world.

The Samba Team said last week that the Microsoft patents cover obsolete elements of the CIFS protocol that Samba does not currently implement in its products. Tridgell said, "The patents do not affect Samba as we do not use the methods described in those patents. The patents cover a particular way of implementing an obsolete part of the [CIFS] protocol. It is quite possible that Microsoft uses these methods in its own implementation, but the methods that are appropriate on a Unix platform are quite different."

The Samba team also said that rather than use Microsoft documentation to produce the Samba software, they used the Storage Industry Network Association's CIFS Technical Reference, which they helped to produce. "The Microsoft document is also very inaccurate in many places. Obviously the Microsoft developers don't use this document when building their own implementations," Tridgell said.

Microsoft was approached by IT Week but declined to comment.

Samba software is an open source file and printer server used in many organisations to manage files for PCs running Windows. It is available for Linux, Unix and VAX server systems. Samba has been available for about 10 years, and from 1993 has been developed under the open source Gnu GPL. The two CIFS patents were issued to Microsoft in 1993 and 1995.

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