Under the current law, a defendant in a patent infringement case can not assert invalidity as a defense in court, but needs to file an invalidation petition with the Patent Reexamination Board.

• 根据现行法律，专利侵权案的被告无法将无效性作为法庭抗辩事由，而需要向专利复审委员会提交无效宣告请求。