[rbanffy]

> Why? There's plenty of permissive F/OSS projects with large numbers of contributors.

Companies invest in developing Linux to create a commodity they can leverage to sell their products and services. The GPL ensures the investment remains a commodity and cannot be used in proprietary products that can't be also leveraged by the initial contributor.

There was a lot of BSD in the core of every proprietary Unix, each tied to a given manufacturer.

[dragonwriter]

> There was a lot of BSD in the core of every proprietary Unix, each tied to a given manufacturer

Except MacOS X, the major proprietary Unixes all predated permissively-licensed releases of BSD, and the early permissively licensed releases were under a copyright cloud for years that prevented anyone from relying on them for commercial downstream distributions.