New Zealand fishing company Sanford denies polluting American Samoa's waters, as the company faces potential fines and confiscations of tens of millions of dollars.
A United States federal grand jury has lodged seven charges against the company under American anti-pollution laws.
Sanford is accused of violating the Act to Prevent Pollution from Ships, as well as conspiracy and obstruction of justice related to accusations it has been illegally dumping oily bilge waste at sea.
The indictment says Sanford operates the fishing vessel San Nikunau which delivers tuna to a cannery in American Samoa and has been routinely dumping bilge oil since at least 2007.
Sanford is also charged with failing to accurately maintain an oil record book for the vessel, obstruction of justice for presenting false documents and deceiving the US Coast Guard during an inspection.
Managing director Eric Barratt told Radio New Zealand's Checkpoint programme his company did nothing wrong and he is ready to defend the claims.
"Sanford takes its responsiblity to respect the ocean and its resources extremely seriously. We'd never permit discharges of pollutants of the ocean and we wouldn't obstruct any reasonable investigation into any allegations.
"So, we absolutely reject these allegations and we'll be vigorously defending all the charges."
Mr Barratt says he does not know where evidence for the allegations came from, but is happy to comply with authorities.
If convicted, Sanford could be fined up to $US500,000 on each charge, with the indictment also seeking criminal forfeiture of more than $US24 million.