From Longman Dictionary of Contemporary Englishbe bound (by something)be bound (by something)PROMISEto be forced to do what a law or agreement says you must do → bindingbound (by something) to do something The Foundation is bound by the treaty to help any nation that requests aid. You are legally bound to report the accident. → bound
Examples from the Corpus
legally bound• Conversations or agreements may however leave the parties morally if not legally bound.• Home helps felt that they are being legally bound not to care!• Where a person has voluntarily chosen to undertake an economic transaction, he is legally bound to complete it.• The company was also legally bound to promote competition in the industry and ensure electricity supplies met standards of supply and quality. 