Capital allowances were available for expenditure incurred on a variety of studies (including surveys) carried out in the years before wind farms became operational. 

The appellant companies owned and operated offshore wind farms. They claimed capital allowances on expenditure incurred on a variety of studies (including surveys) undertaken as part of the environment impact assessment carried out in the years before the windfarms became operational. HM Revenue and Customs (HMRC) issued notices denying the allowances. The appellants appealed. The First-tier Tribunal (FTT) concluded that the appellants were entitled to capital allowances in relation to some of the costs of the studies. HMRC appealed. The Upper Tribunal held that the appellants could not claim capital allowances or make deductions from their profits. The appellants appealed.  

The Court of Appeal had to consider the following issues: (i) The extent (if any) to which