Some suppliers of SaaS services reserve the right to vary contractual documents without notice by posting revised versions on a specified website address (but otherwise without notice) from time to time. Can such variations (in business to business contracts) be valid and what grounds for challenge might a customer raise?

The Contractual terms

To establish that express terms and conditions have been incorporated into a contract, the party seeking to rely on them must show that it has done what is reasonably sufficient to give the other party notice of them: Thornton v Shoe Lane Parking Ltd and Parker v South Eastern Ry. This will be a question of fact in each case. The more onerous or unusual the terms, the more that needs to be done to bring them to the notice of the other party: Interfoto Picture Library v Stiletto Visual Programmes and J Spurling Ltd v Bradshaw. For further information, see Q&A: Is it sufficient from a contractual perspective to state that a copy of terms and conditions can be viewed elsewhere