That's quite possible.
I would suggest a good rule of thumb when things are unclear is: "Don't charge money for it"...unless you find you *can*.
If you find that you *can* charge money for it, then the rule becomes: "disclosures are your friend".
Make it clear that you don't know if the issue is in question and you believe it's public domain, but if it's not, you'll do something to fix the problem. Don't show your hand by saying *what* you'll do-just make it clear that you'll do something.
If, however, you suddenly find it's *raining buckets of money*, see rule three, which is: "Hire a lawyer to protect yourself, and then hire a second lawyer to protect you from the first one".
Oh and don't forget to send me my advisory fee-at 5% of the gross, it's reasonable enough
Disclosure to the proceeding (above) statements: I am not a lawyer, in any shape or form, nor am I a person, or a sueable entity, as pertains to any laws that would allow anyone to sue me. I do not-infact-exist. I live-if I lived, which I do not-in a place beyond all laws, mortal or immortal, guarded by a vicious dog, and I spend all my free time polishing my shotgun.