Is the affixing of a seal on the documents signed by a business corporation required?

The Quebec Business Corporations Act and the Canada Business Corporations Act do not require the use of the seal. The documents are "signed" by the representatives, for and on behalf of the business corporation, in order to bind the latter and not "sealed". The seal can however add, for some persons, an "official" or "authentic" character to the documents of the business corporation, but it adds nothing to their validity.