Certain rights of trade unions depend on the number of members they have. For example, the number of people covered by special protection against dismissal, and the number of hours of time off work available for trade union activities. This number also indicates the level of popularity of the trade union among employees and, in certain cases, may result in a trade union organisation losing certain rights.

Twice a year, i.e. by 10 January and 10 July, every trade union is required to provide the employer with information on the number of members who are employees, and people performing work under civil law contracts (e.g. mandate contracts or B2B agreements).

The information on the number of members should reflect the level of union membership as of 31 December and 30 June, respectively.

If the trade union fails to provide the employer with information on the number of members, it loses the rights of a workplace trade union organisation. The trade union itself continues to exist, but the employer is no longer required to cooperate with it. That means trade union representatives do not benefit from trade union protection and that the employer may introduce or amend internal regulations applicable in the company without involving that trade union.

If an employer has doubts regarding the accuracy of the data provided, it may raise an objection to the trade union to have the court verify its membership numbers. If such an objection is submitted, the trade union has 30 days in which to apply to the court for verification of its membership. If it fails to do so, it loses the rights of a workplace trade union organisation.

A request by the employer to verify membership numbers does not constitute hostile action against the trade union. It is a standard procedure whereby all the parties involved have more certainty when entering into social dialogue regarding the scope of rights held by the organisation operating at the employer’s premises. There are situations where trade union membership documentation is not properly maintained, and court verification of these documents is the only way to establish the actual number of trade union members.

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