CASL and Email Signatures (Canada)

Canada's Anti-Spam Legislation, known as CASL, has applied to commercial electronic messages since 2014. A commercial electronic message is one whose purpose, or one of whose purposes, is to encourage participation in a commercial activity, and section 6 of the Act requires such a message to have consent, to identify the sender and anyone on whose behalf it is sent, to give contact information, and to include an unsubscribe mechanism. Most one-to-one business email is not marketing, and CASL also exempts certain messages, such as many messages sent between organizations that have a relationship and that concern the recipient's business. Signatures matter in two ways. First, a full signature with the legal business name, mailing address, and a phone, email, or web contact covers the identification part when a message is commercial. Second, a promotional banner or offer in the signature can add a commercial purpose to an email that would otherwise be purely transactional, so organizations emailing Canadian recipients should consider CASL when deciding what their signature promotes. Unsubscribe links are normally handled by marketing email platforms rather than the signature, which is why promotional content is safest in campaigns built for that purpose.