In March 2006, Medtronic was awarded Patent No. 7,018,407 -- a patent related to a tricuspid heart valve holder. This case is interesting because the patent stems from an application originally filed 24 years earlier in 1981.
In 1988, the applicant appears to have lost an interference proceeding regarding some of the claims. The next correspondence comes 16 years later with an Ex Parte Quayle action that would lead to the 2006 allowance.
According to Alan Harrison, an Intellectual Property Analyst at Nerac, the PTO has also granted a further extension of 1109 days "for the delays in adjudication of the interference."
Enforcement of pre-1995 patents has an additional twist regarding pre-existing use. Again, Alan Harrison:
35 USC 154(c)(2) REMEDIES moderates enforceability by prohibiting injunction, damages, or award of attorney fees against uses "commenced or for which substantial investment was made" during the pendency of the application prior to June 8, 1995 (pre-existing use).
But Medtronic still may sue competitors who continue their pre-existing use, and to continue such use those competitors must make equitable REMUNERATION under 35 USC 154(c)(3). Following Bristol-Myers Squibb Co. v. Royce, 69 F.3d 1130 (Fed.Cir. 1995), Medtronic may alternatively require deferment of FDA approval for infringing devices during the enforceable life of the patent.
It is unclear whether this patent has any commercial value -- and whether its submarine style emergence create other prosecution laches problems.