Microsoft Corp.'s European Union contracts are under investigation for whether they meet EU privacy standards, the second such probe into its government contracts since 2018.

The European Data Protection Supervisor April 8 launched an investigation into whether contracts between Microsoft and EU institutions comply with the General Data Protection Regulation. A 2018 privacy investigation in the Netherlands “is bringing to our attention some important elements when it comes to” Microsoft products, EDPS spokesman Olivier Rossignol said in an email.

The...