Former Owner
- T. Royer1
- T. Whitcombe Greene1
- Tammaro De Marinis1
- Taschen von I. Kossel. R.1
- That Guy with the Books1
- Thomas Bateman1
- Thomas Gage1
- Thomas Johnes1
- Thomas Windus1
- Thomas de Grey, 2nd Earl de Grey1
- Vittorio Forti1
- W. F. Olis1
- W. J. Gilbert1
- Walter Paul Havens1
- Walter Wehle Naumburg1
- Ward Murphey Canaday1
- Wilfrid Voynich1
- William Augustus White1
- William Bateman1
- William Betham1