Interesting answers, and I appreciate them. I might make a suggestion that we as artists might want to consider.
I for one want to post my collection of ACEO's on my website, a kind of personal gallery, if you will. I think there may be other collectors who wish to do the same.
I might suggest that artists who believe that this is acceptable include language as to such in their postings, and include a release for non-commercial use with the sale. I for one will not be bidding on any other ACEO until I can get that permission from the artist up front. That's going to be a real hassle for me, but since I own the artwork I consider posting the image in a non-commercial way as fair use.
Others will disagree, and that is their right. there will always be artists who have a fear of posting images, etc.
But I have to tell you, I've made my living in intellectual property rights for 30 years, and even I think that the permissions issue has gotten completely out of hand. Wearing my collector hat now, it seems absolutely ridiculous that I have to scramble around for 35 permissions to post on my website images of art that I purchased for my collection. (What would happen if I opened a museum and took admission? Do museums pay royalties to artists for exhibition of paintings in their collections? That's an honest question--I don't really know.)
Of course, with my artist hat, I don't want the art used to launch a series of greeting cards without my permission.
There has to be a reasonable place in the middle short of requiring permissions of every single artist after the fact, which is why, as a group, I put these ideas to you for your comments.
Kind Regards
Thom