Sherman v. The Queen, 2008 DTC 3069, 2008 TCC 186, aff'd 2009 DTC 5681, 2009 FCA 9 -- summary under A

A warranty provided by a vendor of software rights to the taxpayer respecting the achievement of a business plan was commercially unrealistic. The taxpayers had the right upon such breach of warranty to return the software to the vendor in satisfaction of their obligation to pay the deferred purchase price. In these circumstances "the only reasonable interpretation is that the agreement was intended by the parties to give the appellants the right to walk away from the arrangement at any time within the first year" (para. 129), so that the cost to them of the software was only its nominal value.