Usually, for the top-of-the-line coins in each type, they say the list of owners with the words "Ex." preceeding it.
I would think the gallery won't give out that information. Sometimes, bidders are anonymous until they reveal themselves later, if at all (i.e., the 1933 Saint in 2002, the 1927-D Saint I saw auctioned at FUN 2020). This "Harte" collection isn't as famous as the Garrett, Price, Eliasberg, etc. collections that we see on the lineage of other coins. I haven't seen the name before but I'll double-check the Bowers' GUIDE BOOK.
It's NOT on the list of the 5 top-end 1907 High Reliefs auctioned through HA because I cut-and-pasted a few of those into my Saints PDF. Could be others I didn't see (and if this was cleaned and/or a lower grade, that would eclipse the ownership of TR and his daughter in terms of making the coin valuable) and/or it could have gone to Stacks or another auction house. The 5 high-end 1907 HR's I included in my Saints PDF were all MS-68 or above, except for the Flat Rim MS-67.