Many questions are posted with copyrighted images included. These are generally images from well known aviation photo websites that Aviation.SE users have uploaded to Imgur—with the copyright banner still right there at the bottom.
Examples of such image use can be found here, here, and here, ...and you get the idea.
(By the way, let me just say that I'm not trying to pick on any particular users; to find the above examples I systematically went through the newest several score of questions and found any instances of obvious copyrighted images.)
The Stack Exchange Network Terms of Service makes it clear that users shall not contribute copyrighted material to SE (a user is called a "Subscriber" in the legal jargon). See this excerpt from §3:
Subscriber represents, warrants and agrees that it will not contribute any Subscriber Content that (a) infringes, violates or otherwise interferes with any copyright or trademark of another party
Now, one might plead that this is fair use, but this is clearly not the case, at least for US jurisdiction. Fair use is determined by four factors; instances such as those I highlighted above clearly do not pass factor 3,
- the amount and substantiality of the portion used in relation to the copyrighted work as a whole
since the copyrighted photos are reproduced in their entirety.
How should we respond to such copyright infringement?
Should we just ignore it until the copyright holders file infringement claims?
Should we militantly pore over every post on the server and remove all copyrighted material?
Should we flag new instances of infringement or otherwise draw attention to the misuse?