If a due diligence petition is filed during the 180-day period following publication of the regulatory agency determination of the regulatory review period, the regulatory agency (e.g., FDA) makes the determination under 35 U.S.C. 156(d)(2)(B) whether the applicant for patent term extension acted with due diligence during the regulatory review proceedings. The term “due diligence” is defined in 35 U.S.C. 156(d)(3) as “that degree of attention, continuous directed effort, and timeliness as may reasonably be expected from, and are ordinarily exercised by, a person during a regulatory review period.” After affirming or revising the determination of the regulatory review period, the regulatory agency notifies the Office and publishes the results in the Federal Register. If no comment or petition is filed in the time period provided, the regulatory agency notifies the Office that the period for filing a due diligence petition pursuant to the notice has expired and that the regulatory agency therefore considers its determination of the regulatory review period for the product to be final. Following notification from the regulatory agency, the Office will proceed with the final eligibility determination. See 21 CFR Ch. 1, Subparts D and E.