(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.
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:
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.
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!