Patent systems throughout the world can be divided into first-to-file countries and first-to-invent countries. A U.S. Patent is granted to the first inventor. Consequently, properly recording your invention is essential to establishing your early date of invention.

In order to establish an early date for when you made your invention, you should explain and record your invention in a written or printed document, preferably one that includes sketches, prints, photographs, and/or diagrams. This document should be signed and dated by the inventor(s). In addition, you should explain your invention to least one person who is not an inventor, and that person should sign and date the written description of your invention, confirming that: (1) he/she signs as a witness to the document, (2) the invention has been described to him/her, and (3) he/she understands the invention. Note: the sole act of witnessing the signature of the inventor(s) is not sufficient. The non-inventor must also understand the invention so he/she can later testify to its existence at that early date.