Dealing with the commons is a fashionable subjects in nowadays Italian legal literature; the article is a critical review of this trend. It point out that an analysis of the nature of the specific common involved is logically preliminary to the choice of the legal attribution. It point out further that the present legal categories of public resources law has lost its meaning; the idea of common resources is thus promising in order to provide a new foundation of open access to a common pool of assets both material and immaterial. The relevant field of discussion is of course Intellectual Property. In the last centuries academic investigations have paved the way to a incredible increase of public knowledge; this common pool of ideas is now under the way of a new kind of enclosures. The conception of commons can provide a promising doctrine to challenge the privatization of common knowledge.