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Ski Patent Slap Fight: Armada vs. Rossignol vs. DPS vs. The Rest of the Skiing World

(This is a long article, most likely of interest only to obsessive alpine skiers, or people interested in the gory details of patent litigation.)

Warnings and Disclaimers!

  • I am not a patent lawyer. My opinions have no legal weight or standing.
  • This article is entirely my opinion, including all pronouncements about the business practices of various ski manufacturers, and all summaries of information contained in patents.
  • I have no financial or other business interest in any company mentioned here.

If you have factual corrections or additional information, please leave a comment and I’ll do my best to revise accordingly.

The Situation

It’s possible to patent nearly anything these days…and the ski industry has finally joined the tech industry in patenting tiny, obvious innovations (often over blatantly obvious prior art) and using them to beat on their (usually smaller) competition. The current slap fight is over who owns the patent on various configurations of rockered skis.

Most skis are cambered, meaning that when set base to base, a pair of skis will only contact each other at two points, one very close to the tip and the other at or very close to the tail.

“Tip rocker” and “tail rocker” are simply a longer and/or more pronounced tip and tail, where the contact points move closer to the center of the ski. This K2 catalog page illustrates camber, rocker, and various combinations of the two. Click it to zoom:

If this seems obvious to you, you’re not alone: the Altai of Siberia have been making skis like this for thousands of years.

(Top and right photos by David Waag, courtesy of offpistemag.com. Click the images to read the stories associated with them.)

Currently, Armada has sent “cease & desist” letters to several small, independent ski manufacturers for breaching their patent on certain types of rockered skis. Finally they sent one to Rossignol, who has fired back with a lawsuit based on their own patent that predates Armada’s—and lurking in the background is a Drake Powderworks (DPS) patent.

[Side note: what makes US patent fights interesting is that they are based on first to invent, not first to file, and court proceedings are usually necessary to determine when an invention was actually conceived.]

The Rossignol Patent: 6,986,525
Priority date of original application: September 29, 2003 (claims benefit of French patent filed October 15, 2002)

Rossignol’s broadest claim is to have patented a ski tip where the widest point of the tip is between 5 and 15mm off the snow.

They refine this claim with many different claims on specific geometry. This is standard practice for patent applications, because if prior art is found for the general case, the patent holder can still claim these more specific cases. Some of these refinements include:

  • Making the widest part of the ski tip between 40mm and 90mm from the contact point
  • Making the widest part of the ski tip between 8mm and 12mm off the snow
  • Making the widest part of the ski tip between 100mm and 120mm wide
  • Making the entire tip (measured from the forward contact point) 150mm to 190mm long

They go on for quite a while with various combinations of geometry claims which I won’t enumerate.

Rossignol also claims specific rockered tail geometry measurements, but only as refinements of the 5mm-15mm rockered tip claim.

  • Making the widest part of the ski tail between 1mm and 50mm off the snow
  • Making the widest part of the ski tail between 2mm and 100mm forward of the rear contact point
  • Making the widest part of the ski tail between 85mm and 120mm wide
  • Making the entire tail (measured from the rear contact point) between 2mm and 100mm long

And so on.

The Rossignol claim only refers to the “forward contact point”, so flat camber (or “zero-camber”) skis may also be covered…though this is unclear, since there is no longer a single “forward contact point”. This is the sort of issue that keeps lawyers employed.

The Armada Patent: 7,690,674
Priority date of original application: August 10, 2006

The Armada patent claims a bewildering variety of combinations of skis, bindings, and a heretofore-unseen system where the camber can be changed by tensioning a cable run between the tip and tail.

(Interestingly, Rossignol has previously developed such a cable system and used it in prototypes for the Phantom SC108, though it is not clear whether the system was originally designed before or after Armada’s patent filing, and the design never went into production. Thanks to Vitamin I for this information.)

Armada’s first and broadest claim is on a rocker-camber-rocker ski, with the transitions between rocker and camber “also coinciding with the sidecut transitioning from concave or straight to convex and also being the widest regions of the device.” They refine this claim with a number of specific geometry claims.

The problem with this claim is that it is self-contradictory. It is geometrically impossible for a ski with significant sidecut (as over 99% of skis are) for the sidecut to transition from concave or straight to convex at the “widest region of the device”: a ski with concave sidecut will still be getting wider at the point where the sidecut transitions to convex, and the widest point will be a significant distance away from this transition because it is difficult to construct a ski with sharp kinks in its sidecut profile. Here’s an illustration of the problem:
Sidecut Transition Vs. Widest Point Of Ski
Therefore, the only ski that can possibly fall under this patent is one that has little to no sidecut, because for any other ski, only one of the two points (concave->convex transition, widest region) can coincide with the rocker/camber transition.

Armada makes a similar claim on the same style of ski with a binding already attached, but worded differently: “wherein substantially all of the sliding surfaces coinciding with the non-concave portions of the sidewalls are rockered and substantially all of the sliding surface in the central portion is cambered.” They also refine this claim with a number of specific geometry claims.

Finally, they make a strange claim on the same style of ski which does not have any limitations on relative position of rocker vs. sidecut, but which has more tail rocker than tip rocker. (Claim #32.) I don’t know of any ski built to these specifications.

Interestingly, the original application on which the final patent claims priority (Application 11/463,828) makes a much broader set of claims that basically cover all rockered skis. Apparently Armada had to retreat from these claims, most likely due to prior art.

The Drake Patent: 7,690,674
Priority date of original application: November 1, 2007

Drake’s patent is simpler: they claim the five-point sidecut, both for skis and snowboards (i.e. a long enough rockered tip and tail to require a separate measurement for tip and tail width) with a turning radius of the body between 50 and 115 meters.

They refine this claim with several more specific geometry claims, including:

  • Sidecut of 81-115 meters
  • Body width of 90-180mm (for skis), 250-375mm (for snowboards)
  • Tip width 80-180mm (for skis), 275mm-300mm (for snowboards)
  • Tail width 70-160mm (for skis), 275mm-300mm (for snowboards)

And so on.

[Note: I think these clauses are to avoid possibly being invalidated by XC skate skis, which have a variety of strange sidecut shapes but are all very skinny.)

So: Who Wins?

It’s very difficult to tell whose patent actually predates whose—because as previously mentioned, US patent disputes are decided by provable date of invention, not date of filing. So I’ll talk about who potentially infringes whom, but without a legal process of discovery this necessarily remains my own speculation.

DPS vs. Armada and the world

Based on the published sidecut numbers (135-133-134), the Armada ARG infringes on the Drake (DPS) patent if the Armada ARG’s effective edge is between approximately 55cm and 84cm. Armada doesn’t publish effective edge figures for the ARG, but reader ‘Vitamin I’, in the comments, claims it to be about 78cm, which would fall under the Drake patent if correct.

I don’t know of any other skis that might infringe the DPS patent due to its very specific limitation on sidecut radius. Note that the DPS patent postdates the Armada patent even though the DPS ski predates the ARG, so date of invention is likely to be an issue.

Armada vs. The World

The Armada patent appears to be the broadest, because it covers any rocker/camber/rocker ski—but with two versions of a limiting clause which requires the transition between rocker and camber to happen either exactly at, or very close to (“substantially all”) the transition between sidecut and tapered tip/tail.

Unfortunately for Armada, and as I mentioned before, the first patent claim is written in such a way that it is impossible for any ski with significant sidecut to fall under it: the only ski I can think of that might fall under it is the DPS Lotus 138. (Which came out before the ARG, Armada’s direct copy of its shape.) Tough luck for Armada. But let’s move forward and assume that neither judges, nor juries, nor lawyers understand basic geometry.

Even if you give Armada’s fundamental mistake a free pass, skis like the Hellbent appear to not infringe, because their rocker transition is a long way away from the sidecut transition. Neither do K2’s other rockered tip skis like the Obsethed, because the widest point of a K2 tip is generally at the very end, well off the snow and putting the sidecut transition outboard of the camber/rocker transition. The Surface Live Life, One Life, and any other traditionally-shaped ski with tip and tail rocker added are also in the clear.

The BD Megawatt is off the hook due to having flat camber (also called “zero camber”), as is any other flat camber ski.

I can think of several skis that might infringe if you ignore the fundamental impossibility of Armada’s claims, but I’m not going to list them, as Armada started this whole slap fight and I don’t want to give their lawyers any ideas.

Rossignol vs. The World

The Rossignol patent claims a very specific limitation on tip shape and configuration: the widest point of the tip must be between 5 and 15mm off the snow. (Their claim on tail shape is much broader, but is a dependent claim of the tip shape.)

Standard practice in the industry for many years was to to place the widest part of the tip exactly at the forward contact point, both for standard skis and “rockered” skis, which is most likely why Armada claims it in their patent. Unfortunately this isn’t a measurement that ski manufacturers ever publish, so it’s impossible to tell whose skis might infringe without physically measuring them.

Interestingly, Rossignol has apparently showed no interest in enforcing their patent, despite the existence of many likely infringers, until Armada recently started attempting to enforce their own patent. Rossignol has not, to my knowledge, gone after anyone but Armada. (Please leave a comment if you have information you wish to share.)

And, in fact, Rossignol’s complaint against Armada alleges both obviousness in light of prior art, and an inadequate description of the invention as per 35 USC 112, first paragraph, which is consonant with the issues I’ve outlined here.

Armada vs. Rossignol

Rossignol most likely has priority of date with their patent, so this comes down to the exact positioning of the widest part of Armada’s potentially infringing skis. Since this is not a published measurement, I would have to measure them myself to come up with a number. (Rossignol specifically claims in their letter of complaint that the ARVw infringes.) If anyone has that measurement for various Armada skis (or if I find it), I’ll update this post.

Note that even if Armada is ruled to have infringed Rossignol’s patent with their skis, their own patent still remains in force: witness Ellsworth’s patent on “Instant Center Technology”, which is a special subset of the Horst Link bicycle suspension patent (owned by Specialized). Despite their own patent, Ellsworth still has to pay royalties to Specialized, and anyone who wants to use Ellsworth’s patent (which Turner did at one time) must pay royalties to both.

Prior Art

Here’s where things get even more complicated.

The first obvious case is the aforementioned Altai tribesmen in Siberia, who have been making rockered skis for thousands of years. However, since many of the claims involve very specific geometry measurements, the skis are handmade with primitive tools, and the tribesmen treat skis as a consumable item, it might be difficult to find skis with such specific measurements and to prove their date of manufacture. Also, there may be an issue with such skis never being seen or used in the USA…though since I’m not a lawyer, I can’t comment on the ins and outs of this issue.

However, similar skis eventually came to America. This photo of Snowshoe Thompson, an American mail carrier of over 100 years ago, appears to show skis with tip rocker, as does the statue in his honor:

But again, this will be difficult to prove. Perhaps someone has a pair above their fireplace?

The second, and more useful, obvious case is ZAG Skis, who have been selling alpine skis with rockered tips since the 2003-2004 ski season (and which were most likely designed long before, Stephan “Zag” Radiguet having founded the company in 2002). The Gold 93, Freeride 84 Big, and Freestyle Backcountry were commercially available long before anyone else thought to patent any sort of rockered ski: see reviews, and small pictures, here. Additionally, they were skied in the USA no later than February 2004.

Unfortunately I don’t have a pair of any 2003-2004 ZAG skis available to me, so I can’t measure where the widest point of the tip ends up relative to the snow contact point. Good measurements here would be very useful in testing the validity of both Rossignol’s and Armada’s patents—although I suspect that the multiple clauses of the Rossignol patent are designed specifically to get around the geometry of the ZAG skis, so that even if the first, broadest claim is invalidated, Rossignol would still hold patents on a variety of geometries.

The third, less obvious case, is that by 2004, many different ski manufacturers had already transitioned from old-school pointed ski tips, where the widest point was at the forward snow contact point, to the more blunt, rounded tips seen on many modern skis, where that point is pushed forward. It may very well be that the widest point of some of them is between 5mm and 15mm off the snow, invalidating part or all of the Rossignol patent. (I’m thinking specifically of Blizzard, Fischer, Head, Stockli, and Volkl, but there may be others.) Furthermore, it may very well be that the transition between sidecut and tip taper is in a place that invalidates Armada’s patent (even though it is self-contradictory).

In fact, I have an old pair of Volkl G4s, made with various topsheets and under various model numbers starting in 2000, whose widest point of its tip appears, at first approximate measurement, to be 5.5mm off the snow. This alone invalidates the main claim of Rossignol’s patent. Furthermore, the widest point of the tail appears to be a couple mm off the snow, which would invalidate their tail rocker claim, too. (Though most of their specific dependent claims would still remain unless other examples could be found.)

Of course, the skis of Altai tribesmen, several pre-existing models of ZAG skis, and the nearly simultaneous unveiling in 2006-2007 of many different models of rockered ski by K2, Line, and several different amateur ski builders (see this thread on skibuilders.com), supports the idea that these ‘innovations’ are all obvious, and therefore don’t deserve patent protection. But the courts have not been sympathetic to this argument, so I doubt anything will ever be overturned on those grounds.


Assuming that you want to avoid falling afoul of these patents (even if they turn out to be bogus), here’s my reading:

To avoid falling afoul of Rossignol’s patent, make sure that the widest point of your ski tip is not between 5mm and 15mm above the snow. The patent makes no mention of whether this is measured with camber flattened or not: I would assume not, but don’t hold me to that.

To avoid falling afoul of Armada’s patent, make sure that the transition from sidecut to tip/tail taper, and the widest part of your ski, is well outboard of your snow contact points—or use zero or negative camber.

Once again, this article is entirely my opinion and is not to be construed as legal advice.

Thanks for reading—and thanks to all the commenters who have provided additional information so that I can keep this post as accurate as possible!


Permalink: Alpine Ski Patent Slap Fight: Armada vs. Rossignol vs. DPS vs. The Rest of the Skiing World
  • nate

    got some JJs if you want me to measure. also, just want to say this is all BS, armada’s being incredibly ridiculous, and i actually don’t blame rossi for firing back. power to the big(ger) guy, for once.

  • Endre Hals

    Thank you for writing this summary of the situation, patents are (deliberately) hard to read.

    Luckily the Armada patent of a tapered tip that starts in (roughly) the same area as the rocker is not a very good solution in practice, (it makes skis unstable) therefore easy to avoid. The Rossi patent though is harder, but easier to prove outdated, since the problems with these patents as i see it is that they don’t define the differences between a long tip and a rocker (or am I wrong here?)

    Basically you can construct all imaginary shapes between a traditional ski (pre all patents) and the JJ, ARG or S7, and the patents can not tell when a traditional tip becomes a rockered tip or a tapered tip.

    Endre Hals

  • vitamin i

    I think the Armada ARG effective edge is about 78cm, and DPS Lotus 138 192cm effective edge is about 87cm. Not sure how that data affects whose product infringes on whose patent.

  • vitamin i

    Re: Armada’s Claim #32: 2007/08 Armada JP vs Julien had a tail which was 10mm higher than its tip, but that model did not have rocker, so I believe that model is not related to this Armada patent. However, the 2008/09 Armada JJ model replaced the previous JP vs Julien model, and I believe this patent indeed covers that JJ model. However, I cannot confirm whether the JJ model has more tail rocker than tip rocker.

  • vitamin i

    rossi was the one that tried a tensioning cable during R&D phase, but they discarded the idea and never released such skis to the public. the rossi phantom sc 108 model had that cable during R&D phase, and perhaps a few other rossi models during R&D phase (not sure which other models, if any).

  • Powderhound23

    A major claim of this article is that Armada is suing Rossignol.

    That’s not the case, it’s the other way around: Rossi is suing Armada:


    In searching the database, Armada does not appear to be suing anyone.

  • Endre: you are correct in that the primary Rossignol patent claim doesn’t differentiate between a regular tip and a “rockered” (longer) tip…so it’s very likely IMO that prior art will be found. In fact, I may have already found it with the Volkl G4, which by itself would narrow the “no-go” region to 8-12mm of rise.

    That is why Rossi added all the dependent claims on various shapes of rocker: so that if the first, broadest claim is invalidated, they can still claim the subsets of rocker shapes defined by the dependent claims, of which there are many.

    I agree with you that the Armada patent shape (tip rocker starting at the sidecut transition) isn’t the best way to build a ski, and it’s better to continue the sidecut some distance up into the tip/tip rocker.

    You are correct that the patents, for the most part, don’t differentiate between a regular and rockered tip, which is why I wrote the article…because everyone was saying that “Armada has patented tip rocker” or “Rossi has patented tip rocker”, which is not true at all.

    vitamin i: Thank you for the information, both on effective edge and on the Rossi tensioning cable! I’ll update the post accordingly.

    Powderhound23: You’re right: according to the complaint, Armada sent a cease & desist to Rossignol (as well as to several other ski manufacturers, AFAIK) but did not actually file a lawsuit yet.  I’ve updated the post to reflect this.

    However, since Rossi refused to comply with the terms of the C&D, I’m sure a countersuit is coming presently.

  • SEMag

    I think there’s another major player in this game: Volant, with the Spatula designed by McConkey (who probably set the precedent on the reverse sidecut, reverse camber ski). Here is an excerpt from “A guide to the Volant Spatula, the world’s greatest powder ski”:

    “During the summer of 96 at a bar in Las Lenas Argentina while hanging out with some friends I quickly sketched a picture of some fat skis with reverse side cut onto a beer napkin…Then in 1998 the Volant design engineers came out to Squaw Valley…And then the light bulb flashed on. I dug up my old beer napkin and began pondering the concept. I thought about hard snow and soft snow and began comparing the similarities of powder to water. I realized that the effects of riding on powder snow would be very similar to riding on water. Water skis have reverse side cut. So do surf boards. And they both have decamber or rocker…So nothing happened for 2 years. Finally after stewing over it for too long I began talking to the design engineers at Volant about just gong for it and jury rigging a pair or two together in the shop in their spare time. If it wasn’t for the hard work and extra after hours put in by Ryan Carroll and Peter Turner in the Volant factory the first and only four pairs would never have been made in the summer of 2001.”

    Here is the whole thing: http://www.fuzeqna.com/evogear/consumer/kbdetail.asp?kbid=61

    I *think* that the Spatula was the first reverse-reverse ski, and DPS was paying homage to it’s shape with the 138. I don’t, however, know if Volant had any patents in place…

  • SEMag:

    As far as I can tell, the Spatula patent was never granted: the application is available online, but a search of the USPTO database yields no results for any of the inventors in combination with “Ski”. I suspect their application may have been abandoned when Volant basically disappeared a few years later.

  • chrasualBroBomb


    Clearly you’re not a very careful reader. Nowhere in this article is the claim made that Armada is suing anyone. The article states, correctly, that Armada sent several “cease and desist” letters to small manufacturers and Rossignol. The nature of the letter is essentially, “Pay us royalties for using our patented tech, or we WILL sue for damages up to 3x the amount.”

    Rossi THEN filed suit as a response to the letter.

  • David S.

    In Rossi’s lawsuit document, available below, they state that it is “at least” the ARVw, not the ARV as you mention above.


    Thanks for putting out this article. Very helpful.

  • Powderhound23


    The author removed the claim after I posted this and it is in the comments below. He did have it saying that Armada was suing Rossignol. Which seems to just shred the credibility of author right away, that he could mistake the entire situation.

    I love my S7s, and I paid 150 bucks more than the JJs to get them, because I liked the ski way more.

    But it does seem that in looking at patents that Armada applied in August 2006, http://appft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=1&f=G&l=50&co1=AND&d=PG01&s1=%22Ar…..da+Skis%22 so maybe they have a claim here. It would only cause greater competition, meaning lower prices for all. Not sure what the concern is here, Line has a patent on twin tip skis, if anyone actually made a true twin tip, they would do the same thing that Armada did.

    Armada did not patent rocker, camber, or any of that stuff, just merely a combination of them right? It seems like just a few skis copied them, but I assume primarily the S7, that’s why they went after Rossi. Armada has always given credit in press to Shane McConkey for inspiring designs. They just put rocker and made some tweaks and made it way better. Pretty sure the Spatula is patented. Atomic would now own that patent because they purchased Volant.

    Maybe there is just not enough info.

    We will see when the court case comes, but there is just so much need for clarity here.

    I am betting that most objects you own are patented, even the thing you clean your sink with.
    Or better yet, that computer you are on? yep, probably patented too.
    Maybe the tire tread on your car too. I am pretty sure patents are only enforceable for 7 years anyway.

    Patents encourage innovation, not the other way around. People wouldn’t innovate if they could just always copy…

    Like to know your thoughts. You want better skis or are you happy with the JJs and S7s?

    Personally, I would like to see what comes next.

    Still don’t really get why Rossi is suing Armada over the ARW, but I can only assume that it is a power play by a huge company to crush the small one.

  • Powderhound23: If correcting the article in response to your comment ‘shreds my credibility’ with you, what do you suggest I do instead?

    I will continue to update this post to correct any errors I may have made, and to reflect additional facts brought to my attention.

    As far as other ski patents: Line has no patents assigned to them, so I don’t see how they can have patented twin tips. (Please correct me if I’ve missed it.) The Spatula patent has apparently been abandoned, as I mentioned. And the ARG is clearly patterned after the DB/DPS Lotus 138, not the Spatula.

  • Powderhound23

    J. Stanton,

    Sorry, my words may have been a bit harsh, it’s just that the article seems a touch biased.

    Rossignol has over 180 patents. Line for sure has a patent on Twin Tips, that’s common industry knowledge for years. Maybe the patent is now assigned to K2, try that search. and they would cease and desist anyone that made a true twin tip, every ski company has design arounds. For years most ski companies had to pay 5 bucks per pair of twin tips sold to some guy in Seattle and it never was made public knowledge, but this guy got rich and it never affected our prices. He had a patent.

    There are more patents than you think out there in the ski industry, and this kind of stuff is probably pretty common I am guessing. The S7 is so similar, maybe it was the right thing for them to do. I certainly don’t agree with Rossi suing Armada, they should just work it out.

    I am not too familiar with DPS so I cannot comment on whether or not they copied, but with Armada’s team like and the inspiration and proximity of McConkey, it would be unclear as to how or why they could do that. They definitely applied for a patent before DPS, so clearly they were working on it at the same time or before. They have always claimed to have patterned ARG after spatula.

    It won’t make any difference to innovation (it will only encourage) and certainly no difference on price. Rossi already charges WAY more than Armada for the same ski, so they have plenty of profit, because they make their own skis and have a huge factory.

  • Backcountry.com: The

    […] camber skis. Rossignol did not take it well when theirs arrived in the mail. Read about the lawsuit here. var button = document.getElementById(‘facebook_share_link_14979’) || […]

  • Sluggo

    DPS Engineer, Peter Turner, is the same Volant Ski Engineer that worked with McConkey.

  • Dave h

    I am aware of 1985 patent on fully rockered skis and early rise tip and tail designs. The patent was abandoned, but prevents subsequent similar patents. The holder was from Indiana! It is not hard to find in the free search websites, doesn’t anyone do their homework anymore?

  • Dave h

    I’m guessing volant did

  • Dave h:

    For quite a while, the patent office was very lax about searches for prior art.  They've tightened up a lot in the last few years…but there are a lot of shaky patents out there.


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