Originally Posted by JeromeP

I'm not an expert on patent law, but if patent law is being followed correctly, which is debateable consider the history of software related and Microsoft related lawsuits, then Ford could have used and electric a/c compressor.

Patent law is about patenting a product or specific process, not a concept. The concept of electric a/c compressors has been around for a very long time. Home and building a/c is electrically based, so the concept is general knoweldge and implemented in many different fashions by many different manufacturers. Patent infringement could have happened if Ford had directly copied the mechanics behind the Toyota electric a/c system. But if Ford had chosen to take an existing compressor they had around and electrified it, or designed their own and then placed it in the climate system for the vehicle, that wouldn't be patent infringement because they did their own homework and created their own device to acomplish the same goal.