Israel’s richest person Beny Steinmetz sued Global Witness, claiming breaches of his human and data-protection rights as part of a “sustained negative publicity campaign” led by the anti-corruption activist group.

The claim by Steinmetz and three other individuals, who are employed by or associated with his BSG Resources Ltd., was filed at London’s High Court and served on Global Witness today. The claim was brought under the U.K.’s Data Protection Act after Global Witness refused requests to produce personal data on the claimants for almost a year, according to an e-mailed statement.

Steinmetz said the group had made a number of “bogus” claims about BSGR, which is subject to a probe into how it obtained mining rights in Guinea. Global Witness’s chief donor, billionaire George Soros, has advised the West African nation’s government on mining issues, according to the statement.

BSGR has faced a widening investigation involving at least four nations into how it came to control half of Simandou, one of the world’s richest iron-ore deposits. Global Witness has also been examining the acquisition of the rights for more than a year, the group said in an e-mailed statement.

“Global Witness intends to robustly defend its position and regards the claim as an attempt to stifle journalism in the public interest,” it said. “BSGR still has not explained important aspects of its Simandou deal, notably the ownership of secretive companies associated with it. Rather than seeking to bully those raising legitimate concerns, BSGR should address these matters directly.”