In patent law, which is true about a reissued patent?

A reissued patent serves to correct defects in the original patent, such as errors in the claims or the specification. This legal mechanism allows the patent owner to amend the original patent to clarify or broaden the claims and ensure that the patent adequately protects the invention as much as possible. The reissue process is particularly important because it maintains the original priority date of the invention while addressing any issues that may have arisen in the original patent.

Because reissues focus on fixing existing patents rather than creating new inventions, they do not undergo a complete renewal process or constitute a brand-new patent. This directly supports the idea that the purpose of a reissued patent is to rectify problems rather than to introduce something entirely different or new.

The other options do not accurately describe the nature of reissued patents. They are not temporary solutions; they serve a specific purpose in addressing defects within an established patent rather than introducing new inventions or completely altering the claims without addressing the existing issues.