Cold Steel engaging in lawfare again – sends C&D letters to knifemakers over “SAN MAI” trademark (UPDATED)


UPDATE: Lynn Thompson has released an open letter on the issue on Cold Steel’s website. Link below.

Lynn Thompson and Cold Steel have been engaging in a pattern of “lawfare“. Last year, they sued CRKT over their claim that their locking systems turned their folders into “virtual fixed-blades”. While I think that CRKT’s claim was stupid, I have a hard time figuring out how Cold Steel was harmed by the claim. That lawsuit was settled, but Thompson and Cold Steel are at it again. This time instead of trying to hamstring an actual large-scale competitor like CRKT, Thompson has sent the above letter to dozens of knifemakers who advertise that they make “san mai” blades.

San mai blades consist of a smaller piece of hard steel sandwiched and laminated between two pieces (or a trenched single piece) of softer steel. In fact “San mai” means “3 flat things (layers)” in Japanese, and may refer either to the blade itself or the laminating technique used. One problem, Cold Steel trademarked “SAN MAI” in 1987.

I am nowhere close to being a lawyer, but I understand that copyright law is pretty specific. From what I have been reading on sites like Bladesmiths Forum, Thomson doesn’t have much of a leg to stand on. His trademark covers “SAN MAI” (all caps), “SAN MAI III” as well as a stylized logo version of the term. From what people have been saying online (take with a grain of salt) is that legally if one simply says “san mai knives” or “san mai technique” it isn’t actually infringing on Cold Steel’s trademark.


Someone posted this to It has the Thompson letter and the filed trademark.

As I said, take it with a grain of salt, but the consensus is that the Cold Steel trademark only refers to the specific term “SAN MAI” and the logo design. That might be all well and good if you have deep pockets, like CRKT. However,  small makers lack the resources to fight a company the size of Cold Steel. Seeing a case through to the end is likely to yield a Pyrrhic victory. One might prevail, but it comes at too high a cost to survive. It is far more likely that small makers will cave under the threat, and the bully will silence the “competition”. It is far easier to simply to scrub your website than fight “the man(child)”.

Artisinal makers are no threat to Cold Steel, but for some reason or another Thompson seems to think that actions like this actually benefit his company. I have never been a Cold Steel fanboy, but I haven’t gone out of my way to hate on them. They offer a mix of acceptable and overbuilt to complete mall-ninja crap. I am no longer going to sit on the fence. I find Thompson’s actions to be abusive and repugnant. I am through with Cold Steel.

UPDATE: If you would like to hear Lynn Thompson’s side of the story, you can find his open letter on the subject here.


  1. Sam L. says:

    It would then seem that san mai in all lower case would be legit. I had always wondered exactly what was san mai steel, and now I know. If someone said/wrote that their blades were in the Japanese san mai construction, that should be a proper description, and legal, but Lawfarers don’t respect that.

  2. Elcas says:

    Once again cold steel is on the crazy side
    Was looki’g at some of their blades again now it’s gone

  3. Double L says:

    I agree CRKT should have described their lock differently,but my goodness just look at all the bullshit that CS has spread over the years.Dont throw rocks when you live in a glass house.If you think it’s a mess now wait til the patent expires on the tri-ad lock and anyone can copy it.Cold Steel will be as nervous as a virgin on prom night because every little brand out there will copy it if they can.And CS knows it’s the only advantage their folders have over most of the competition,and without that advantage their folders are merely average.

  4. MD Matt says:

    I do not mind the fact that they are protecting their intellectual property. I do mind that they trademarked an industry term in common usage which they had to know was going to put them at odds with a variety of products across the knife-making community. The comparison with the Walker/liner lock is truly bad form. Walker popularized an entirely new design and sought to protect his creation. CS took an existing steel working technique and pinned down 3 specific spellings and associated logos of that technique. CS does not own the technique and did not invent it. Compounding a bad decision with C&D letters simply furthers the impression that you made a bad choice and are trying to make your actions sound reasonable. This is a bad business and I will not be putting any more money in their pockets unless and until Cold Steel gets its act together. Putting up a press release apologizing for being right is not an apology or good enough to earn back my business.

  5. borg says:

    Based on cold steel logic they would have to sue all knifemakers in japan and the world that make this japanese style of knife. What’s next will they trademark the name katana and sue the entire country of Japan for trademark infringement?

  6. AJ187 says:

    What a bunch a babies the people are complaining about this . Whole thread on Bladeforum that always hates Cold Steel anyway and will always find a reason to. They wouldn’t buy their knives anyway, but claim they won’t now because of whatever manufactured controversy comes up. You have to look at the source. They are trashing Cold Steel’s Facebook with 1 star reviews and whining like their 2 year olds. I assume their adults and they need to grow up. Not understanding basic business principals probably goes along with their immaturity. Won’t effect Cold Steel in the least.

    1. Joshua Fields says:

      Well put. Blade forums should call themselves bitch forums with all that whining they do.

  7. Joshua Fields says:

    Don’t like Cold Steel? Simple fix. Don’t buy it and quit crying like a 2 year old sucking on a baby bottle.

  8. Jonathan Davis says:

    I’ve noticed with how eager Cold Steel was to bash the LAWKS design and file suit…but they sure don’t mind copying CRKT’s older lock technologies. The Bush Ranger Lite uses a pretty identical design to Ron Lake’s L.B.S. (Lock Back Safety) design. The Crawford 1 model wears a secondary safety for it’s liner lock so it’s essentially copying the LAWKS.

    Somewhere in the depth of the REKAT Knives threads on Bladeforums I remember reading a post that was about 20 years old. Apparently Lynn Thompson wanted REKAT to grant him licensing rights to use their Rolling Lock design on the Cold Steel brand and they said no. If you read more on REKAT threads all these posts show up about bad customer service by REKAT and reports of lock failure. REKAT went out of business a few years later. It would not surprise me if any of the old thread posts were mostly by Cold Steel employees and/or Lynn himself considering his childish and parasitic nature and the private identity of anonymous forum posts.

    When I look back on the story on REKAT’s demise and the suspicion of Lynn Thompson behind it? I would say it’s possible. But with what the man has done in the past 4 or 5 years to other knife manufacturer’s? yes, I firmly believe now he and/or his staff propaganda posted REKAT out of business through Bladeforums. The guy’s just dirty and I hope when Demko’s patents expire knife designers will cold shoulder him when he starts looking for that new lock design for his brand.

Write a Comment

Your email address will not be published. Required fields are marked *

Cold Steel engaging in lawfare again – sends C&D letters to knifemakers over “SAN MAI” trademark (UPDATED)

button to share on facebook
button to tweet
button to share via email