How do you stop someone from stealing your art and claiming it as their own? You watermark it, just enough so that it doesn’t get in the way of the actual image. How does a developer stop people from violating the non-disclosure agreement and posting screenshots of, say, Guild Wars 2 anonymously? Equal levels of watermarking.
Now, the above is not a screenshot from Guild Wars 2, as posting a screenshot of such feature from Guild Wars 2 even for proof of concept is what my lawyers refer to as “digging myself into a hole” that they will later “shoot and bury me in,” so instead I’m using an old April Fool’s teaser of the Guild Wars commando class. Click on the picture to enlarge it, and you can see my email address watermarked frequently enough that you couldn’t possibly crop a usable picture.
Obviously this doesn’t prevent people from posting their thoughts of the beta test without repercussion, but it does make it impossible to post screenshots without Arenanet taking action against the account.
Reminder to all closed beta players: you’re under NDA. Don’t risk breaking the NDA, you could permanently lose access to all ArenaNet games. ~RB2
MMO Fallout 
ArenaNet,genius all the way.
You’re an idiot that needs a good slap to the face.
Agreed,
I have no idea how that comment slipped by. I’ve deleted it and Brandon won’t be posting here anymore. Then again my family members and dear friends who have Down’s Syndrome may be making me biased.
-Omali
Is this watermark throughout gameplay or just when you take a screenshot? If the latter, what prevents people from just capturing the screen with methods other than the built in screenshot facility?
Throughout gameplay. During play it is subtle enough that you wouldn’t even notice it.
Thanks for the reply. That is indeed a brilliant way to enforce the NDA.