	u k court rules against rtz on oil field costs the u k high court dismissed an appeal by rio tinto zinc corp plc s rtzl l rtz oil and gas ltd unit and ruled that the financial provisions a company makes for the future cost of abandoning an oil field are not tax deductible the press association reported the company was appealing against a decision of the tax commissioners that any such provision was a capital expenditure not a revenue expenditure and was not deductible the court was told that since the company had made an annual provision of around stg for the eventual cost of abandoning a rig an rtz spokesman said the ruling was not worrying as the subsidiary had assumed that the provisions were not deductible from corporation tax payable it would have been a bonus if the company had won but all budgeting had been on the assumption that it would not he said oil analysts said that rtz s assumption of liability was shared by the industry as a whole the ruling appeared to mean that tax relief on the expensive process of abandoning rigs would apply when the expense occurred not when provisions for future expenses were built into the accounts one analyst added reuter 
