U.S. oil giants Exxon Mobil, Chevron and ConocoPhillips challenged over ‘secretive’ tax practices
Oxfam on Monday filed shareholder resolutions against U.S. oil giants Exxon Mobil, Chevron and ConocoPhillips, saying a lack of transparency over their global tax practices poses a material risk for long-term investors.

The international relief charity said the companies' tax practices undermine the public's interest in a fair tax system — especially in Global South countries "with the greatest tax revenue needs."

"Exxon, Chevron, and ConocoPhillips's threadbare tax disclosures leave investors, watchdog groups, and the general public in the dark about the companies' secretive tax practices," Daniel Mulé, policy lead on extractive industries and tax at Oxfam America, said in a statement.

ConocoPhillips confirmed it had received a shareholder proposal from Oxfam and would review it ahead of its annual general meeting in May next year. The company added that it "remains committed to following all applicable disclosure rules in the countries in which we operate."

A spokesperson for Chevron said the company "complies with all applicable tax laws. Our approach to tax matches our efforts globally to conduct our business legally, responsibly, and with integrity."

Exxon Mobil did not respond to a request for comment when contacted by CNBC.

It comes amid a broader push for greater tax transparency from large corporations, particularly as people around the world feel the squeeze of a cost-of-living crisis.

Oil majors have been repeatedly criticized for their global tax operations. And, in recent months, energy giants have faced growing calls for a windfall tax after raking in record-breaking profits thanks to a surge in the price of oil and gas following Russia's invasion of Ukraine.