Dennis,
I've seen this before, and in our case we didn't need to seal the edges because there was no concern of shorting or anything in the end product, this is a choice you will have to make, Does your end product have any protrusions or mounting holes near this exposeed copper...etc.. If you determine you need seal those nasty edges, I'd say Mask 'em, or if your not Smask ready go buy a conformal coating pen and rework it yourself.
One last tip, be sure to inspect those edges, we found that traces close to breakaways were being micro-cracked and busted open by careless operators.
reply »