This post on Harvard Business School's Working Knowledge from Kristen Senz gives us insights into the process of learning by contributing to open source. This comes from a recent study conducted by Frank Nagle, "Learning by Contributing: Gaining Competitive Advantage Through Contribution to Crowdsourced Public Goods."
Kristen quotes Frank saying:
What this study shines a light on is that the companies that contribute and give back learn how to better use the open source software in their own environment. A lot of the research I do looks at the question, can the company be better off but also leave the world better off?
While this study is focused on large organizations, in future research Nagle plans to study the effects of learning by contributing on smaller firms and startups.