ANCHORAGE, Alaska -

The Alaska Supreme Court has affirmed a lower court ruling that set the 2006 value of the trans-Alaska pipeline for tax purposes at nearly $10 billion.

Pipeline owners had argued for a lower figure of $850 million as the value for the 800-mile line and terminal facilities. Owners calculated the figure from fees they collect from oil shippers.

Superior Court Judge Sharon Gleason, who has since moved to the federal bench, ruled in favor of the higher number in May 2010.

Gleason said the pipeline enables production from North Slope oil fields. She calculated the higher number based on an estimated $18.7 billion replacement cost minus depreciation and other factors.

The decision and the higher assessment is a victory for municipalities that tax the pipeline.