Assertion: patent's validity | /r/HasProperty | challenged
Facets:
Source sentences:
text: When a researcher working for a particular company finds something new in the laboratory that could improve a technology already patent protected by that company, filing a patent application can protect the improvement against a competitor, broaden patent coverage in that technology space, and give the company further protection in case the validity of prior patents is challenged.
text: Otherwise, the validity of an issued patent may be challenged as to the priority date of its claims that purport to relate back to an insufficient "provisional".
text: When validity is challenged, the patentee says his patent is very small: the cat with its fur smoothed down, cuddly and sleepy.