On Tuesday, the Court of the Justice of the European Union concluded that Jehovah’s Witnesses who are preaching door-to-door are subject to the same European Union data-protection rules — known as the General Data Protection Regulation — as massive tech companies like Facebook and Google.

In an era of widespread data collection that has seen companies like Facebook amass vast amounts of information about its users, European privacy activists have found a new enemy: Jehovah’s Witnesses.

The Christian-affiliated group is famous for its habit of showing up at front doors and handing out copies of its religious magazine The Watchtower, but in Finland, door-to-door preachers have also been writing down people’s names, house addresses, and religious beliefs so they could use the information for follow-up visits. That is a violation of Europe’s privacy laws, which require consent in collecting personal data, according to Europe’s high court.

After Finland banned the preachers’ unsolicited collection of data in 2013, the Jehovah’s Witnesses appealed in court, arguing that, as Reuters put it, “Preaching should be considered a personal religious activity and as such the notes taken down during such visits are also personal.”

Now, with Tuesday’s ruling, Jehovah’s Witnesses have joined Mark Zuckerberg as the new — but presumably less smoked-meats-obsessed — face of the excesses of Big Data.