...the applicant shall provide the patent number and certify, in its opinion and to the best of its knowledge, ...that the patent is invalid, unenforceable, or will not be infringed by the manufacture, use, or sale of the drug product for which the abbreviated application is submitted. The applicant shall entitle such a certification "Paragraph IV Certification".
Under the Drug Price Competition and Patent Term Restoration Act, or the Hatch-Waxman Act, a company can seek approval from FDA to market a generic drug before the expiration of a patent relating to the brand name drug upon which the generic is based. The first company to submit an Abbreviated New Drug Application (ANDA) with the FDA has the exclusive right to market the generic drug for 180 days.
To begin the FDA approval process, the generic applicant must: 1) certify in its ANDA that the patent in question is invalid or is not infringed by the generic product (known as "paragraph IV certification"); and 2) notify the patent holder of the submission of the ANDA. If the patent holder files an infringement suit against the generic applicant within 45 days of the ANDA notification, FDA approval to market the generic drug is automatically postponed for 30 months, unless, before that time, the patent expires or is judged to be invalid or not infringed. This 30-month postponement allows the patent holder time to assert its patent rights in court before a generic competitor is permitted to enter.