The workers accuse management, their administrative council, which is composed of representatives from national patent offices, of issuing the most patents they can for the sake of making more money.

"Since many of the national offices are financially dependent on the fees resulting from the work of the EPO, decisions taken by the EPO Administrative Council are influenced by the interests of the national patent offices," said the union in a statement explaining their actions, "and the desire for as many patents to be granted as possible."

"Decisions in favour of quantity damage the quality of the patents," the statement continued.

They argue that this is producing a kind of centrifugal force that is pushing a return to national as opposed to European based patenting processes. There are 34 members of the EPO, the 27 EU member states plus other European countries.

"In recent years, there has been a decentralising tendency from the EU office back to national offices," said one representative of the union, who did not wish to be named for fear of being fired, "which is the opposite of the principles of a European Patent Office, and the opposite of what is demanded by users: a centralised, coherent patent office for Europe."

"They are sending work back towards the national offices to maintain a justification for their own existence."

The workers rallied for a number of hours and delivering petitions to the British, French and German embassies in Brussels. They say that their concerns are not for better wages or conditions, but simply the principles of high-quality patenting. Rather than giving patent examiners the appropriate amount of time to investigate an application, they are encouraged to rush through the process.

The following day they met with European Commission officials to discuss their concerns

The action is an escalation of a brief downing of tools last June at the Munich headquarters of the EPO and a rally outside the Swiss Patent Office. The previous year, they had demanded more time to work on their assignments in order to deliver a quality project.

They have also sent a letter outlining their concerns to current president of the European Council, Nicolas Sarkozy, urgently requesting that the EU bodies "rethink the distribution of power in the EPO."

They are also hoping to develop closer contacts with the European Commission, which they feel is understanding of their position, and will be lobbying users of the system, including Business Europe - the trade association representing the largest corporations in Europe, and the European Association of Craft, Small and Medium-sized Enterprises (UAPME).

'Broader malaise'

Management representatives however rubbish the idea that there has been any decline in quality and accuse the workers of being unnecessarily worried about their jobs.

"The figures show that the number of patent refusals is actually increasing - a clear sign of increasing quality," Oswald Schroeder told EUobserver. "If we were just handing out patents like we didn't care, the number of refusals would surely be going down. In some sectors, the refusal rate is up to 90 percent."

Mr Schroeder said that over the last few years, applications have become much more complicated and voluminous, making investigating them more difficult for examiners.

He said that the staff had no reason to be concerned, as they have recently doubled the amount of time they allow to write a refusal (which takes more time than the issuing of a patent).

As to the workers' concerns about decentralisation and a return to a national-based system, Mr Schroeder said: "No examination work will ever be outsourced."

The employees have essentially worked themselves into a lather about nothing, he believes. "[The strike] is just part of a broader malaise against the behaviour of member states in the administrative council [the management board] - they're worried the national patent offices will take away their jobs."