The MSR believed a $US100 million reimbursement from PDCIL's customer, Offshore Kazakhstan International Operating Consortium (OKIOC), for modifications to a PDCIL barge rig, was taxable income because of PDCIL drilling contract with OKIOC.

Despite the court decision dismissing approximately $27 million of the total tax assessment, the Supreme Court did rule in favour of the MSR on other issues, which resulted in a tax assessment of about $US2.3 million against the PDCIL. "However, since PDCIL is currently in an overpaid position with respect to its Kazakhstan taxes, management anticipates there will be little if any tax liability as a result of this decision," Parker Drilling said.