Since patenting first started there are probably thousands of patents that have been filed in respect of compasses globally. However as far as my collection is concerned there are only a few that are worth mentioning here and the main ones in date order are:
Schmalcalders Patent GB3545, 1812
Singers Patent GB1861, 11th June 1861
Hunters Patent US35,156, May 6th 1862
Symons Patent GB3293, 20th September 1875
Patents attributable to Colonel William Willoughby Cole
Verner.
As I research other compass patents, I may choose to add them here in due course.