The Green route to Open Access (OA), meaning the re-publication in OA venues of previously published works, can essentially be executed by contract and by copyright law. In theory, rights retention and contracts may allow authors to re-publish and communicate their works to the public, by means of license to publish agreements or specific addenda to copyright transfer agreements. But as a matter of fact, because authors lack bargaining power, they usually transfer all economic copyrights to publishers. Legislation, which overcomes the constraints of a contractual scheme where authors usually have less bargaining power, may deliver a (digital) second publication or communication right, which this paper discusses in the context of research publications. Outlining the historical and philosophical roots of the secondary publication right, the paper provocatively suggests that it has a “moral” nature that even makes it a shield for academic freedom as well as a major step forward in the overall development of OA.