Patents by their very nature are pregnant with considerations of time. The exclusive rights they afford only last for a finite period- generally from issuance until twenty years from the filing date of the application. Moreover, since patents necessarily engage with the evolution of technology, patents reflect various "snap shots" in time that reflect the state of the art at a particular moment. Patent law must constantly wrestle with time. Many of these topics have been explored extensively in both judicial decisions and the literature. The most obvious example of considering the temporal aspect of patent law is ... obviousness. The courts have discussed at length concerns about hindsight. Because obviousness is assessed at the present time based on the state of the art in the past, the problem may arise that, with the patent in hand, one may inappropriately conclude that the invention is obvious. The literature has explored the hindsight problem both theoretically and experimentally.
Timothy R. Holbrook,
Patent Disclosures and Time,
69 Vanderbilt Law Review
Available at: https://scholarship.law.vanderbilt.edu/vlr/vol69/iss6/2