Dedicated to Protecting Ideas Award-winning intellectual property law, IP strategy services, and advisement. We are passionate about helping you protect your best thinking. Patent of the Month: Vehicle with Frunkgate Frunkgate: US 10,676,137 has issued for something you didn’t know you wanted, a “tailgate” on the front of your car. Learn More Newest Team Member Stephen Liu is a patent attorney licensed to practice before the United States Patent and Trademark Office and the State Bar of Texas, and the newest member to our team.

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Carstens & Cahoon is an award-winning intellectual property law firm. We help mid market clients and venture-backed startups with patent, trademark, and copyright law matters.


Patent litigation, prosecution, international filings, counseling


Trademark acquisition, litigation, and international filings

IP Strategy

Landscape studies, white space analysis, freedom to operate counsel

Possible Limit on the Use of “Common Sense” to Invalidate a Patent Claim for Obviousness Based on a Single Reference

The law regarding obviousness, like a pendulum, has swung over time between favorable to unfavorable positions depending upon one’s perspective.  In 1952, the requirement that an invention be “nonobvious” was codified in Section 103 of the Patent Act.  In 1966, the Supreme Court issued its seminal decision in Graham v. …

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Electric Car

New Apple patent Paves the Way for Passive Alignment and Charging Technology

Recently issued Apple patent utilizing passive alignment technology for charging an electric car that does not require human initiation illustrates a possible solution to one of the many hurdles facing electric cars going mainstream. Filed on May 18th of 2020, granted less than five months later, and titled “Charging station …

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