How much of a commercial solution is really proprietary ?

Question

I look at a lot of open source solutions and commercial solutions.

I was wondering what the legal nature of this is like. Are lot of commercial solutions out there using open source solution's code , and wrapping it up in their rephrased code ? Kinda like linking to the open source library and writing something. How much of a commercial solution is really proprietary ?

Complete solutions, like Apache server vs. some commercial server solution, LAMP vs. ASP .net, etc.

Better example is taking a open source ruby library and writing my own and selling it

Answer 1

Open source doesn't always mean "take this and do whatever you want for free". The source is licensed and can only be used according to that license, any other use is copyright violation.

Cases of "rephrased code" should be analyzed on case-by-case basis. Sometimes you just can't rewrite something really differently - like linear search in an array. Also algorithms can't be subject to copyright - only their implementations, so you can reimplemenet any unpatented algorithm and that will not be a copiright violation.

Yes, many commercial products use open sourse solution. For example, if you need a simple embedded database you will most likely just use SQLite - it' free (public domain) and of high quality - since chances you will write a high quality database on your own and in reasonable time are quite slim.

Answer 2

In all cases read the license, don't assume anything. It's not possible to generalise.

Lawyers make a fortune litigating this sort of thing. It could be said that only the lawyers profit from litigation.

Judges generally don't understand the technical details. Why should they, they started out as lawyers.

This is not legal advice. Treat it with a grain of salt. These were all generalisations.