The U.S. Tax Court has denied a request by the Internal Revenue Service that it issue a partial summary judgment concerning Medtronic’s Cayman Islands subsidiary in an ongoing tax case against the medical device titan.

At issue are certain transactions Medtronic (NYSE:MDT) made among its various units during the tax years 2005 and 2006. Medtronic is disputing the IRS’s adjustments of those transactions.

The IRS had asked the tax court to issue a partial summary judgment on Medtronic’s claim that its Cayman Islands subsidiary, Medtronic Puerto Rico Operations Company (MPRCO), bears all of the product liability risk for Medtronic’s cardiac rhythm and neurology businesses. The IRS has disputed that claim.

The Tax Court said it could not issue a summary judgment because certain facts were still in dispute.

"Upon due consideration of the parties’ arguments, it appears that there are material issues of fact in dispute regarding respondent’s (IRS) three grounds in support of granting the motion for partial summary judgment. Consequently, resolution of the issue in this motion upon summary adjudication is not appropriate," wrote Judge Kathleen Kerrigan in the order.