Date of Invention

The earliest of the following dates:

(a) the date the inventor filed either a provisional or non-provisional (full) application or

(b) the date the inventor can prove he or she built and tested the invention in a NAFTA or WTO country or

(c) the date the inventor can prove he or she conceived of the invention in a NAFTA or WTO country and diligently reduced it to practice.

Filing an official provisional application creates a filing date for your invention. This filing date establishes the date of invention and protects you from other inventors who might claim to be the first ones to have discovered your invention. The filing date serves as proof to the U.S. Patent Office that you in fact created the invention.