The word patent is derived from the Latin pateo, meaning to be open or
exposed. During the medieval period, ‘letters patent’ were frequently used
by monarchs and other sovereign powers to confer various awards such
as lands and titles, or to create new rights and privileges, such as the right
to incorporate. These awards were a matter of public record, hence the
need for them to be ‘patent’, that is, open to scrutiny. In time, letters
patent were also found to be a convenient way of awarding privileges to
foreign craftsmen who were willing to share craft technology. These form
the earliest precursors to the modern patent grant; in England the first
such examples are the letters of protection awarded in 1331 to Flemish
weaver John Kempe, on the condition that he instruct native apprentices.
1 The patent was confirmed by a 1337 statute that accorded safe
conduct and the king’s protection to any other foreign weavers who
wished to settle in England.2