BIM33525 | Stock: valuation on discontinuance of business: stock not transferred to another trader

From HM Revenue & Customs · Business Income Manual

and

Where trading stock is not transferred to a UK trader, the closing stock value to be used is defined as the `amount which it would have realised if it had been sold in the open market’. This is the net amount realisable by disposal of the stock in bulk under practical business conditions. It does not imply a ‘fire sale’, but the price that the goods would have fetched at the normal time for sale.