We have information which leads us to believe that these paintings were started and/or completed by Sir Oswald but we have found no validated documentary evidence. Once we have confirmed the existence of any of these we will move them into the main lists.
| Title | Date | Location |
| "The Seven Sisters" | Birling Gap | |
| York. The Bishop of | Thorpe Underwood | |
| Chatsworth (Duke and Duchess of Devonshire) | ||
| Plummer. Mayor of Eastbourne | ||
| Merrweather-Post. Mrs, (Kellogs) | ||
| The Astors at Hever Castle | ||
| Carew-Pole. Lady | One of the last finished paintings | |
| Chalmondely. Lady | ||
| Westminster. Duke of | ||
| Lynn. Miss Olga (Lady in the Fur Coat) | ||
| Londonderry. Lady (Col. Pike) | Gilling, West Yorlshire | |
| Rotner. Guy | Newton le Willows | |
| Halifax. Lord | Garaby Hall | |
| "Powis Castle" | Herberts. Earl of Powis |
There were also three unfinished paintings at Charleston at the time of the sale in 1980.
If anyone has any details of the above and can confirm or deny their existence we would be very grateful if you would communicate this information to us.