Oh yeah, he's also cherry picking the postcard series and Old School. I guess Topps doesn't care about the fact that these paintings need to sell to keep the product going. Maybe he's just displaying them in the office for a little while or maybe he's stealing them. Someone should look into it.
Plan - are you just speculating that someone is lifting artwork, or do you have some specific information that leads you to believe this, as opposed to some other explanation.
I understand that, if you do have some inside information, you many not want to reveal specifics - but if you're speculating, based only upon the fact that select pieces are not being sold (or returned), I hope you'd indicate that. Based on that fact alone, I think there are other plausible explanations.
I spent five years handling artwork daily as an editor on the X-Men, and personally, if I had thought that someone at the office was stealing that work - they'd be scum. Beyond stealing, my boss cemented the idea that as an editor, even asking an artist for a page (a fairly common practice among editors, I believe) was unethical, because as freelancers, they'd feel pressure to give it up, and giving that artwork to an editor was possibly taking food off their table. Due to that ethical line, I didn't end up with much of any artwork from the books I oversaw - I did get a few unsolicited birthday gifts over the years, I'm happy to say.
There was only one instance of original artwork theft during my years at Marvel, and sadly, the culprit was a thirty-something freelancer who would often visit the offices, looking for work. Little did we know he was availing the hospitality to steal. It was pretty messed-up.
Not a pleasant memory.