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Norway’s sovereign-wealth fund has dropped U.K. security firm G4S Plc from its portfolio, citing abuses of migrant-worker rights in Qatar and the United Arab Emirates.

The central bank in Oslo, which manages the $1.1 trillion fund, said it took the step “due to unacceptable risk that the company contributes to or is responsible for serious or systematic human rights violations,” according to a statement on Thursday.

Shares in G4S dropped as much as 3.7% in London trading. The fund held a 2.33% stake in G4S at the end of 2018, valued at the time at about $91 million. The investor currently has 156 companies on its exclusion list.

The decision to exclude G4S follows a recommendation from Norway’s Council of Ethics, which said it had assessed the company’s operations in the two Gulf countries. The investigation showed that migrant workers have paid recruitment fees to be able to work for G4S, that a substantial part of their salaries went to pay debt related to those fees, and that many were paid less than agreed. In the Emirates, workers saw their passports confiscated, the Council said.

The probe also revealed that workers were exposed to long days, a lack of compensation for working overtime and instances of harassment, the Council said.

Norway’s wealth fund, the world’s biggest of its kind, is managed according to a set of ethical principles. It’s barred from investing in tobacco and certain kinds of weapons, and in companies responsible for serious environmental damage or human rights abuses.

See list of excluded companies

(Adds reference to size of stake, exclusion list)

To contact the reporter on this story: Mikael Holter in Oslo at mholter2@bloomberg.net

To contact the editor responsible for this story: Tasneem Hanfi Brögger at tbrogger@bloomberg.net

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