Overseas Shipholding Group (OSG) filed papers to separate its international and US flag tanker businesses, taking a major step toward a long-mulled spinoff.

The New York tanker owner said the transaction would involve hiving off OSG International (OIN) as a stand-alone company with its own listing during the second half of the year.

The company filed a Form 10, which registers new securities, with the US Securities & Exchange Commission (SEC).

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