Ideally, scholarly objects would be available without constraints on how they can be used. The reality is different, however, and in many cases limitations do apply. These limitations should be clearly indicated for each web resource that is part of a scholarly object and they should be discoverable by both human and machine users. For humans, this can be achieved by embedding easily recognizable logos that convey the license that applies. For machines, this can be achieved by using appropriately typed HTTP links that point at the URI of the license that applies. Once licenses are exposed in this manner, tools such as reference managers can convey this information to humans that use the tool and store it in their database. Crawlers that are on a digital preservation or data mining mission can act according to the constraints imposed by the license when deciding whether to collect and how to further handle a resource. The use of common licenses, such as those provided by the Creative Commons, makes it easy for both humans and machines to readily understand which constraints apply.