Microsoft XML patent sparks outrage

Software developers are angry that Microsoft has been granted a patent for the conversion of objects into XML files.

The patent, which was granted by the US patent office on Tuesday, is for XML serialisation and deserialisation - the conversion of a programming object into an XML file and vice versa.

XML, an open standard developed by the W3C, is commonly used for representing data structures in applications that exchange data. As applications will often need to convert between programming objects and XML files, this patent could cover virtually any application that uses XML to transfer data.

Wookey, a developer on the free Linux distribution Debian, said the patent should not have been granted and could be used by Microsoft to discourage competition.

"It's an abomination to anyone who does programming that the concept of every possible way of converting between a programming object and an XML file (and vice versa) can be owned by one company," said Wookey. "Should someone else want to save a programming object in the form of an XML file, Microsoft can now charge them for the privilege or simply refuse them permission to do it at all in the US."

Michael Tortolano, a senior software manager at Home Media Networks, agreed that the patent should not have been granted.

"Interoperability is the life blood of the computer industry yet we keep seeing software patents being granted which directly threaten the ability of computers to do their basic job, to share and manipulate data," said Tortolano.

Microsoft had not responded to a request for comment at the time of writing.

Although such a patent is less likely to be granted in Europe, which has a less liberal patent system than the US, there are concerns that this could change if the European software patent directive is adopted by the European parliament. Opponents of this directive, which is due for a final vote in the summer, claim that it will lead to the widespread patenting of software in Europe.

A spokesman for the Foundation for a Free Information Infrastructure said that data conversion patents have already been granted by the European Patent Office (EPO); for example, SAP was granted such a patent last year. This patent, EP1267277, is described as a method for "modifying the data structure used by an application program to access database systems in a computer system".

"This [Microsoft patent] once more shows that the practice of the US and European Patent Offices is quite similar," he said. "It is clear that by codifying this EPO practice in a directive as the [European] Commission and Council want to do, they will only make this sort of US-style patents enforceable in Europe as well."

The Microsoft patent that developers are concerned about is patent number 6,898,604 , which was filed in June 2001.

Ingrid Marson writes for ZDNET UK