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Supreme Court rules Lexmark sales exhausted patent rights domestically and internationally

"The basis of the patent exhaustion doctrine is when a patent owner sells a patented product the patent owner can no longer control that item through the patent laws — its patent rights are said to have become exhausted. The purchaser and all subsequent owners are free to use or resell the product just like any other item of personal property, without fear of an infringement lawsuit."

"The two questions about the scope of the patent exhaustion doctrine that were presented in Impression Products v. Lexmark, were: (1) Whether a patentee that sells an item under an express restriction on the purchaser’s right to reuse or resell the product may enforce that restriction through an infringement lawsuit; and (2) Whether a patentee exhausts its patent rights by selling its product outside the United States, where American patent laws do not apply."

"With respect to the first, relating to the Return Program cartridges, the Supreme Court concluded that Lexmark exhausted its patent rights in those cartridges the moment it sold them. The Court further observed that while the singe-use and no-resale restrictions may be perfectly clear and enforceable under contract law principles, they do not entitle Lexmark to retain patent rights in an item it has elected to sell. Once a patent owner sells an item it has enjoyed the rights secured by the limited monopoly[1] provided by the patent, the Court explained citing to Keeler v. Standard Folding Bed Co., 157 U. S. 659, 661 (1895)."

Why Radar Detectors Matter More Than Ever

"DeMuro thought his detector would thwart any potential speeding tickets? Condoms break sometimes. Does that mean no one should use them? Hey Doug, what do you think will happen if no one uses detectors anymore? I’ll tell you. A large minority of Waze-tagged speed traps will disappear. Why? Because the cop hiding behind a bridge can’t be tagged by Wazers who aren’t looking for him. A detector may be the only warning of their presence. Power detector users — the ones using Waze at the same time — are therefore Wazers’ best allies."

Basic overview of how a DC/AC Power Inverter works

For about 15 years now, I've had a inverter that takes high-amperage direct current supplied by a battery or alternator, steps it up and converts it into alternating current for use with typical household appliances, like lighting that I use at camp.

I had a vague idea of how inverters worked, but I never knew the exact electronic process. I thought all of the voltage change was done on the alternating current side of things -- once the modified sine wave is created. It turns out that it's actually the direct current that is stepped up using a Boost Converter (a device that uses an inductor coil to step up DC voltage), while the alternating current sine wave is created towards the end of the process.

A very interesting video. I also encourage you read up about direct-current Boost Converters and their step-down equivalent, the Buck Converter.