The onewheel design using a hub motor on a large wheel is quite distinctive and novel. The patent publication date also has nothing to do with when Changzhou m

The onewheel design using a hub motor on a large wheel is quite distinctive and novel. The patent publication date also has nothing to do with when Changzhou may have begun development -- OneWheel launched at CES 2014, 2 years ago getting A LOT of media coverage as well as a million dollar crowdfund campaign. That makes it rather attractive to knock off. The start date on Changzhou's development was anytime after January 2014. You copy the product in the market, not necessarily the patent itself. It is at your peril to copy so directly and ignore "Patent Pending". It would not take more than 3-6 months for a company like this to have a knock off to show. I have not looked at Kamen's patents, but it would be hard to imagine the OneWheel displacing a Segway's use case. Of course if Kamen's patents well cover the core "self-balancing" technology he could push to get royalties. It would be a waste of money for Kamen to completely shutdown a skateboard though. The OneWheel launched before the hoverboards started showing up. The timeline may even place hoverboards as less blatant derivatives of OneWheel.