I don't know when it started, but the check valve is a fram pattent, which is expired, and pretty much all filter manufacturers are making check valve filters. The idea is to keep the oil from draining into the pan while sitting, and you get immeadiate oil to the bearings at startup. Nissan, GM, Ford ETC. make cars, not oil filters, nor do they make oil. These sort of components are made for the auto makers, to an engineering spec. by the lowest bidder. This is why I use Amsoil 100% synthetic with a fram Tough Guard filter. I'm not putting that many miles on the car yearly to demand bianual oil changes, so I change in the spring as winter is the time when the most condensation accumulates in the pan, synthetic oil allows the water to desolve, or be suspended in the oil as solution, and not seperate like conventional oil. Amsoil claims that you can run their product for 10K miles between changes, don't think I would go that far.