Companies are using information gleaned from chamber of commerce (KvK) files to target the self-employed via Facebook, broadcaster NOS said on Wednesday.

This means that small firms and the self-employed see adverts on their private Facebook pages which relate to their business interests, NOS said.

Car makers Toyota and Lexus among the companies which use KvK information via a middle man advertising agency. This means, for example, a person who makes a living writing text will see a different car advert than a self-employed plumber.

Health insurance company CZ and telecom company Ziggo also use KvK information to target people on Facebook, NOS said.

The KvK has sold information about companies to third parties for years, using an opt out system for new firms rather than the legally-required opt-in.

However, new privacy rules which come into effect on May 25 will make it more complicated for third parties to process other people’s data and sharply increases the fines for firms who break the rules.

The KvK said in a website statement that information its registers is public information but that it has sought a meeting with the Dutch privacy watchdog Autoriteit Persoonsgevens this week to make sure it operates legally.