According to Powder.com, the Marker Kingpin binding has recently been taken off the market due to a “patent infringement lawsuit brought forth by G3 Genuine Guide Gear Inc.”
Marker admitted in court that they had infringed on 1 of 3 patent claims, but the courts will decide if Marker infringed on the other two patents and ultimately determine damages. This case is pending.
For full details, Powder.com and WildSnow.com are the best sources of information. If you’d prefer to read the full legal document, it can be found here.
The Kingpin Binding was released in 2015 and offered a tech toe with a reliable heel piece. It is now unavailable and is not listed on MarkerUSA.com, but it is listed on Marker.net and is still available for purchase at numerous online retailers.