On Facebook, the most common unacceptable behavior involves some abuse of our communication tools. This can be as innocent as annoying others with too many messages or friend requests or as serious as deliberately trying to spam others for commercial gain.
We take these deliberate spam attacks seriously and devote a tremendous amount of our engineering time and talent to build systems that detect suspicious activity and automatically warn people about inappropriate behavior or links. Because of our efforts, only a very small percentage of people who use Facebook has ever experienced spam or a security issue.
Every once in a while, though, people misunderstand one of these systems. They incorrectly believe that Facebook is restricting speech because we've blocked them from posting a specific link or from sending a message to someone who is not a friend. Over the years, these misunderstandings have caused us to be wrongly accused of issues