If the Internal Revenue Service has its way, corporate executives may need to start tracking their hours as carefully as lawyers do.

A ruling by the U.S. Tax Court prohibited a company from deducting the portion of its officers’ salaries attributed to the work done on a friendly acquisition. The court held further in the March 8 ruling that due diligence and other investigatory costs relating to a merger also could not be deducted. Norwest Corp. v. Commissioner of Internal Revenue, No. 25613-95.