Staff from the European patent office in Rijswijk are planning to demonstrate against the sacking of two collegues and the demotion of a third, broadcaster Nos says on Thursday.

All three are union activists and based at the patent office’s headquarters in Munich. Lawyer Liesbeth Zegveld, who represents the union, says the issue is one of ‘pure intimidation’. Workers complain they have no rights. ‘We’ve got a sort of secret service which controls the staff,’ one worker told Nos.

Some 2,700 people work at the office, making it the biggest international organisation in the Netherlands.

Their supporters say they are being made to pay for the ‘tyranny’ of patent office boss Benoît Battistelli. He, however, says intervention was necessary because the three were not abiding by the organisation’s rules and had brought it into disrepute.

Today’s demonstration in The Hague involves a march from the French to the German embassies.