What is the significance of the date of invention?

The significance of the date of invention is primarily centered on when an invention is first conceptualized and reduced to practice. This date is crucial in patent law because it establishes the timeline for determining priority among inventors. Having an understanding of when the invention was first made allows an inventor to assert their rights against other potential claimants and helps to resolve disputes over who was the first to invent.

In the United States, especially prior to the implementation of the America Invents Act (AIA) in 2013, the date of invention was particularly important in the context of determining who had priority in disputes. The inventor who could prove they made their invention first typically held the rights to the patent, regardless of who filed first. Therefore, understanding when an invention is reduced to practice—meaning it has been developed into a usable and working model—was essential for asserting rights over the invention.

This understanding also plays an important role during patent prosecution and litigation, as it helps clarify timelines when examining prior art and determining the novelty and non-obviousness of the invention compared to what was publicly known at that time. The other options relate to the process of patenting and enforcement but do not adequately capture the foundational importance of the date of invention in establishing patent rights.