My employer (IBM) allows people to do things in their spare time with the following kinds of exceptions (off the top of my head, sure there are more):- a) Do n

My employer (IBM) allows people to do things in their spare time with the following kinds of exceptions (off the top of my head, sure there are more):- a) Do not use company time or equipment. Pretty obvious that one. b) No doing something that competes directly with IBM. This has to be more specific than "working with computers". It means I can still get beer money for helping friends/family fix their computers/servers, but I can't start a small consultancy that aims to take possible business away from IBM. I can start a social sports related side project website because IBM aren't in that space. But if I worked on Websphere Application Server (I don't!) I couldn't contribute to, for example, Apache Tomcat/Geronimo or JBoss AS. I could write my own game Apps and sell them through the App Store. Etc. c) Contributing to OSS in your spare time needs to be cleared with IBM, just in case. The main reason is that everyone loves to sue IBM and OSS is fertile ground given the various OSS licenses and implications. If I do some work on some OSS package in my spare time it means I'm tainted in that area. If I then do any work on a commercial application in the same area then it opens the door for people to claim that the commercial work I've done has some work that could have been influenced by the OSS code and part of the commercial application is therefore derivative of the OSS work. With some OSS licenses this could mean that the entire commercial application is considered a derivative work and, depending on the license, the source code would need to be released or IBM could not charge for the software, etc. It's not all doom and gloom. I work with some people that have got clearance to work on OSS software, they just have to make sure they avoid working with anything related to it on the commercial side (to the point of not having access to the source code to provide plausible deniability). You also need to think in advance and not work on anything that we could reasonably be working on in the future. We are also regularly warned to avoid even looking at any OSS related to the commercial code we work on, for fear of tainting. Same for Googling for answers to technical questions and copy-and-pasting code from SO or elsewhere. You've generally got no idea of the copyright/licensing aspects of any code you see in the results. IBM does use OSS in some of its commercial applications. Its use is always cleared with the lawyers first though. Certain licenses must be avoided simply because they are incompatible with selling commercial software. Where the license is permissive we always make sure we follow the rules and I've personally contributed many bug fixes in the OSS code back to the community as required (or even if not required!); these have often been found as the result of formal code inspections (which IBM is effectively funding by paying employees to perform it), peer review, static analysis tools, or general SQA testing.