Corporations have been using their leverage to sue people who criticize their products or practices.   The point of these suits is to bully critics, forcing them to remain silent.    While sometimes a bold consumer is able to evoke the "Streisand Effect," more often the consumer does not want to risk a life-sucking fight with a corporation and retreats into silence.  

Ultimately we would like to see a strong federal anti-SLAPP law.    Until then, we can do our best to encourage corporations to not resort to bully tactics. 

Please feel free to message me with corporations to add to the list, and feel free to put this in the comments as well.    The list will involve any companies which have taken steps to silence online critics.  

To learn more, there's a number of good resources.  For example 

https://www.eff.org/deeplinks/2012/07/case-federal-anti-slapp-statute

http://www.anti-slapp.org/

http://www.thefirstamendment.org/antislappresourcecenter.html

http://www.popehat.com/

http://mlrcblogsuits.blogspot.com/

http://cldc.org/organizing-resources/slapp-suits/