BIM33605 | Stock: non-trading transactions in stock: ways of disposing of or acquiring stock
From HM Revenue & Customs · Business Income Manual
Stock can give rise to a profit or loss by:
sale,
appropriations to and from stock,
insurance claim for part or total loss,
barter transactions,
use in the construction of a fixed asset,
write off of all or part due to obsolescence or slow moving, see stock valuation (BIM33100 onwards),
fall in net realisable value, see stock valuation (BIM33100 onwards),
theft or other loss.
The tax value at which stock is disposed of, or acquired, depends on whether the disposal is in the course of the trade or otherwise.