Emerson Knives are synonymous with their ‘wave,’ the famous self-opening feature that allows a blade to be instantly deployed as the knife is drawn from a pocket or sheath. It’s the fastest way to open a blade – a practiced user can withdraw the knife and lock it open in a single fluid motion. It’s also valuable intellectual property that Emerson Knives has protected with a longstanding patent. In January, Emerson was granted a registered trademark, which is not restricted by time limitations. Emerson Knives’ founder Ernest Emerson announced the news via a post on BladeForums: “the ‘Wave Shaped Feature’ is now a certified and registered trademark #4,879,356 of Ernest Emerson in addition to our ownership of the patent of the wave feature.”
Utility patents are usually granted for 20 years. Having patented the wave in 1997, Emerson’s rights to the wave were slated to end in 2017. According to Emerson, the successful registration of the trademark gives Emerson Knives ongoing ownership of the wave: “Our ownership and right to defend ownership of the feature now extends indefinitely which we will continue to do with full effort,” Emerson said in his post.
Emerson has shared the wave with other knife companies through licensing agreements. Spyderco makes versions of their Endura, Delica, and Matriarch models with the Emerson Wave. Zac Brown’s knife company, Southern Grind, Zero-Tolerance, and Kershaw sell knives with the feature as well. Kershaw recently introduced a new line of affordable Emerson-designed knives that offer the wave, including the new CQC-9K.
Emerson Knives is not the first company to trademark an opening mechanism on a folding knife. Spyderco also defends its round opening hole with a trademark, saying it is their “most recognizable feature.” The company cuts the iconic round hole into all their blades, even fixed blades or two handed openers like the Spyderco Roadie, introduced in 2015.
Ernest Emerson has said that the wave was conceived by happenstance. The first knife to feature the wave was originally designed by Emerson for a team of Navy SEALs. The SEALs had asked Emerson to include a blade guard to catch an opponent’s weapon in case they ever had to engage in bladed combat. While testing the prototypes, Emerson and the SEALs quickly realized that the guard caught on their pockets, opening the blade as the knife was drawn.
Knife featured in image: Kershaw Emerson CQC-3K