One problem with collecting this stuff so haphazardly over so many years is that almost none of it has any kind of provenance. I get something from someone who collects all sorts of film memorabilia in order to resell it to the one person who might want a particular item… and that’s generally as far back as it goes. No information as to the genuine origin of anything. So, most of what I can say about any item is from observation and inference.
This is an 8 x 10 inch black and white negative transparency, containing an approximately 9 1/2 x 6 1/4 inch image of the poster side of the two-sided promotional foldout designed by Seiniger & Associates, with the addition of the words “suitable for mature audiences.” That’s a description and as much as I can swear to being actual fact. Based on that, I’ll say that since this sort of transparency was used to print ads in newspapers and magazines, this was used to print an ad promoting Times Square in a publication aimed at movie theater owners and bookers. I don’t know of any such publication, but it’s hard to believe that such a thing did not exist, and may yet exist. So there may still be out there a catalog of all the upcoming movie releases for 1980 that you may want to run at your theater, containing an extra full page ad for Times Square before the poster design was finalized. Or maybe not, since until such a thing turns up there’s no evidence this ad actually ran anywhere.