In this Aug 28, 2019 photo, the logo of Facebook is displayed on a tablet in Lille. (DENIS CHARLET / AFP)

Facebook Inc won a temporary halt to a demand by European Union investigators to turn over vast amounts of data, potentially frustrating efforts to build an antitrust case against the US tech giant.

The EU started examining Facebook’s sales platform and how it uses data from apps last summer, as part of a broader crackdown on Silicon Valley. It adds to a probe into how Amazon.com Inc collects data from retailers through its platform and investigations into Apple Inc’s app store

The EU General Court suspended the European Commission’s requests for information including data Facebook deemed as “highly sensitive personal information,” according to two decisions dated July 24.

Facebook sued the Brussels-based commission on July 15, citing “the exceptionally broad nature” of the EU’s orders. It also filed two challenges seeking a court suspension of the EU data demands.

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The court president in his July 24 orders said while EU data requests “may unavoidably include personal information, it is important to ensure that confidential treatment of such information is safeguarded, especially when the information does, at first sight, not appear to have any link with the subject matter of the commission’s investigation.”

The court will need to check what protections the commission has in place, Marc van der Woude, the tribunal’s president, said in the decisions. A preliminary suspension is needed “to prevent a situation whereby the contested material is disclosed in violation of the fundamental right to privacy of the applicant’s management and employees.”

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Facebook declined to comment and the commission’s press office didn’t immediately respond to an email seeking comment.

Facebook’s EU lawsuits come as Chief Executive Officer Mark Zuckerberg is preparing to be grilled July 29 over antitrust issues by US lawmakers.

‘Medical Information’

Details sought by the EU in May include “highly sensitive personal information such as employees’ medical information, personal financial documents, and private information about family members of employees,” Tim Lamb, a Facebook lawyer said Monday about the lawsuits. “We think such requests should be reviewed by the EU courts.”

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The EU told Facebook to look for internal emails and other documents that mentioned some 2,500 search terms such as “big question,” ”shut down” and “not good for us” that would also have netted personal communications from employees and work and security evaluations outside the scope of any investigation, according to a person familiar with the case who spoke on condition of anonymity.

Facebook offered to allow the EU to see the sensitive information in a secure environment known as a data room, but that was turned down, the person added. The commission in Brussels earlier said it “will defend its case in court,” adding that its investigation into Facebook’s “potential anticompetitive conduct is ongoing.”

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Once the EU court has heard both sides, it will give a final decision on the company’s so-called interim measures requests, while Facebook’s main appeals remain pending. Any outcome on the interim measures could be appealed.

The cases are T-451/20 and T-452/20 Facebook Ireland v Commission.