that’s normally the mark for an unregistered third-party effect/plugin. to get rid of it you’ll need to register it.
if you’ve already paid for it, you should have a registration number and instruction on how to enter it. if you don’t have the number, try contacting the company’s support to get it re-sent to you, or to find out how to register their software… each company is a little different.
if you haven’t paid for it, then you’ll need to to remove the watermark.
Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW