[beejiu]

> Clearly this is not a contract

I'm pretty sure making a pledge of this nature does form a contract. The terms of that contract are available here: http://www.google.com/patents/opnpledge/pledge/, which says:

> It is Google’s intent that the Pledge be legally binding, irrevocable (except as otherwise provided under “Defensive Termination” below) and enforceable against Google and entities controlled by Google, and their successors and assigns.

[graeme]

A contract typically requires consideration between two parties. Consideration can be almost purely nominal, but it has to exist.

http://en.wikipedia.org/wiki/Consideration