- Protection through Secrecy or Copyright: open source software is protected by copyright. closed source software is protected also by the secrecy of the source code, which requires a complex reverse engineering. It is easier to create from zero a solution without ever knowing that it is violating a patent.

- Complexity of Patent Handling: software is very complex, a single application can contain hundreds or thousands of different patents. It is very expensive and hard to know if my own software is violating any patent even if I wrote everything from zero.

- Univocity: what can we do if the solution of a problem is unique or simple/obvious? When there is no real invention behind, when it is possible to prove that most researches (challenging the same problem without knowledge of the patent) after a short time come to the same solution? It is correct to offer a patent in such case where just the first company who use and patent a simple or unique solution will be the "only" owner?.

- Benefit for few: only bigger companies have the economical resources (and so the advantage) of registering the patents of a software.