CLAs neither enable the kind of enforcement you mentioned, nor do they offer any additional legal protection mentioned in other comments. CLAs are good for exac

CLAs neither enable the kind of enforcement you mentioned, nor do they offer any additional legal protection mentioned in other comments. CLAs are good for exactly one thing, which is to provide an "out" regarding obligations that the license imposes. For example, if a project chooses GPL, a CLA can allow the benefitting org to disregard the share-alike clauses it contains, i.e., effectively allowing the org to use third-party contributions under non-reciprocal terms as if it were licensed to the project steward under, say, MIT- or BSD-like terms, or to relicense the project to a different, incompatible, non-GPL license in the future. Alternatively, a CLA for an Apache-licensed project allows the benefitting party to ignore Apache's termination clauses. These things create an asymmetric balance of power. Anyone operating under different beliefs can only be relying on a cargo-cult misunderstanding of what CLAs are actually about. There's no other reason to use a CLA.