What does the term "prior art" refer to in patent law?

The term "prior art" in patent law refers to any evidence that an invention is already known, which is correctly identified as the correct answer. Prior art encompasses all public knowledge that exists before the filing date of a patent application. This can include published documents, previous patents, public uses, or any other information that could demonstrate that the invention was known or obvious to someone skilled in the field before the application was submitted.

Prior art is crucial because it helps determine whether an invention meets the criteria of novelty and non-obviousness, which are essential for patentability. If an invention is found to be similar to prior art, it may not be granted a patent, as it fails to meet these criteria.

The other choices miss the broader definition and implications of prior art. For instance, evidence of an invention not protected by any patent does not encompass the full range of what constitutes prior art, as it focuses only on unpatented inventions rather than including all types of knowledge. Similarly, patents that have been rejected do not serve as prior art since they do not reflect publicly available knowledge before a certain date. Lastly, the idea that prior art is defined solely by the patent applicant is incorrect, as prior art consists of external knowledge that exists independently of