Cuno Engineering Corp. v. Automatic Devices Corp. Case Brief
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Case Brief Summary & Legal Analysis
tl;dr: The Supreme Court invalidated a patent for an automatic car cigar lighter, finding that combining a known cordless lighter with a known thermostat did not constitute a patentable invention but was merely the work of a skilled mechanic.
Legal Significance: This case is famous for articulating the stringent “flash of creative genius” standard for patentability, significantly raising the bar for what constitutes a non-obvious invention. This standard was later superseded by the Patent Act of 1952.
Case Facts & Court Holding
Key Facts & Case Background
Respondent, Automatic Devices Corp., held the Mead patent for an automotive cigar lighter. The prior art included “cordless” lighters where a removable plug containing a heating coil was manually held in a socket to complete an electrical circuit until it was hot enough for use. Separately, thermostatic controls were widely used in other electrical appliances like toasters and irons to automatically interrupt a circuit upon reaching a predetermined temperature. The Copeland patent had even applied a thermostat to a non-removable cigar lighter. The Mead patent combined these two concepts: it added a thermostatic control to a cordless, removable lighter plug. This new device automatically broke the circuit and released the plug to an “off” position when the heating coil reached the proper temperature, eliminating the need for the user to manually hold it and guess when it was ready. Petitioner, Cuno Engineering Corp., was sued for infringing this patent. The core issue was whether Mead’s combination of existing elements constituted a patentable invention.
Court Holding & Legal Precedent
Issue: Does the combination of existing and well-known elements from the prior art—a removable “cordless” lighter plug and an automatic thermostatic circuit breaker—into a single device constitute a patentable invention under patent law?
No. The patent claims are invalid because the combination of a thermostatic Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint o
IRAC Legal Analysis
About IRAC analysis
IRAC (Issue, Rule, Analysis, Conclusion) is the structure professors expect in exam answers. Each LSD.Law brief states the issue, the governing rule with citations, the court's application of that rule, and the conclusion - the same reasoning pattern you will use on exams and in practice.
Legal Issue
Does the combination of existing and well-known elements from the prior art—a removable “cordless” lighter plug and an automatic thermostatic circuit breaker—into a single device constitute a patentable invention under patent law?
Conclusion
Cuno established the stringent "flash of creative genius" test for invention, significantly Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veni
Legal Rule
To be patentable, an improvement must not only be new and useful Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo cons
Legal Analysis
The Court, through Justice Douglas, invalidated the Mead patent by applying the Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. Lorem ipsum dolor sit am
Flash-to-Full Case Opinions
Flash Summary
- A patent is invalid if it combines known elements in a