When Google decided to do Android, they didn’t go and copy Apples iOS sourcecode. They didn’t have to – Google have enough great engineers that they could do their own implementation of iOS’s features; the value of Apple/iOS is in the ideas and the execution.
While a lot of people have ideas, they usually lack the technical ability to bring them to fruition, and even if they do, they might miss the elegance and finesse of a truly awesome solution. Copying source code means you are already behind the curve, you are not gaining anything, instead you are teaching your team that plagiarism is of higher value than innovation. Followship instead of Leadership.
Teach your team to be innovative, to execute ideas well, and you can publish your source-code on a public forum if you want*
*Never publish your source-code, but THINK of it as published, that will make you run faster and become less complacent.