Former Owner
- William Musgrave1
- William N. Bullard1
- William Noel-Hill, 3rd Baron Berwick1
- William Roscoe1
- William S. Spaulding2
- William Salloch217
- William Salloch (Firm)1
- William Stuart1
- William Targ1
- William Thynne1
- William Trench1
- William Tyssen-Amherst, 1st Baron Amherst of Hackney1
- William Wadden Turner1
- William Wentworth-Fitzwilliam, 7th Earl Fitzwilliam1
- William Wix1
- William Young Ottley9
- Winifred A. Myers Autographs Ltd5
- Winslow Lewis1
- Wolfgang G. Scholz1
- Wolfgang Sigismund, Graf von Gallenberg1