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The problem of fake numbers #584904
02/10/15 5:32 pm
02/10/15 5:32 pm
Joined: Nov 2011
Posts: 4,432
U.S.
Magnetoman Online content OP

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Originally Posted By B31 Ally
What really annoys me is somebody trying to pass something off as genuine factory built original, selling it to an unsuspecting buyer for a vastly over priced sum only for the buyer to later find out they were conned.
I took the liberty of copying the above from another thread in order to start this one. The issue of detecting faked/restamped engine, frame, and gearbox numbers is one that I've thought a lot about for quite a few years and recent discussions on this forum prompted me to take the time to implement several ideas that come directly from my professional life.

Gold Star engine numbers are on the top of the left crankcase, frame numbers are in one of three locations depending on the age, and gearbox codes are on top of the center "slice" (also, less obviously, on the back of the "slice"). As a pretty much worst case scenario, let's say an unscrupulous person has paperwork that matches neither an engine nor frame and has a set of stamps with a font that matches the ones BSA used. So he restamps all three pieces to make it a "matching numbers" bike with RRT2 gearbox, thereby adding many thousands of Dollars/Pounds/Euros to its selling price. Variations would be turning B33s and B34As into Gold Stars, A7s into Rocket Gold Stars, TR6s into Bonneville TTs, etc.. Can this fraud be detected by a potential buyer before parting with their cash?

The answer to the above question almost certainly is 'yes,' and it now would take me less than a few minutes. The only reason I qualified my statement with an 'almost' is that I don't want to try to predict what might be possible if someone is willing to expend $10,000 worth of effort to increase the selling price of a motorcycle by $5000.

Anyway, I now have the necessary set of tools and techniques and have tested them on Gold Star engines and all three types of frames (however, they're much more broadly applicable than just to Gold Stars). But, in a very real sense, so what? Posting details of the tools and techniques only would encourage unscrupulous people to try to rise to the challenge, and it's not like I'm volunteering to fly around the world being the Gold Star Truth Squad. The only use I can think of for this is if I'm ever in the market for yet another motorcycle at least the odds of me being burned by a restamped one are now pretty small.

On the other hand, I could try to find a partner to put up the money for a few patents for what I've developed and set up a business together focused on the car world where serious money changes hands. Meanwhile, though, "pass[ing] something off as genuine factory built original, selling it to an unsuspecting buyer for a vastly over priced sum only for the buyer to later find out they were conned" remains as a general problem for potential buyers to be very aware of.

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Re: The problem of fake numbers [Re: Magnetoman] #584921
02/10/15 6:38 pm
02/10/15 6:38 pm
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rick e. Offline
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Earth

Does it involve:

1) magnetism and metal particles? (ferrous frames)

2) HF waves and grain structure ?

3) oxide layer thickness and hardness?

4) thin film deposition and surface energy?

5) material that glows in the dark?

5) Witch doctor bones?

Shop humor guesses aside, hope you tell us more....

Re: The problem of fake numbers [Re: rick e.] #584936
02/10/15 8:14 pm
02/10/15 8:14 pm
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Magnetoman Online content OP

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Originally Posted By rick e.
Does it involve:
1) magnetism and metal particles? (ferrous frames)
2) HF waves and grain structure ?
3) oxide layer thickness and hardness?
4) thin film deposition and surface energy?
5) material that glows in the dark?
5) Witch doctor bones?
You guessed correctly. It's all of the above, but especially no. 5) and no. 5)...

Originally Posted By rick e.
Shop humor guesses aside, hope you tell us more....
Given that patents cost ~$10k each to pursue it's unlikely I'll take that route. But, any prior publication would rule it out entirely so it's best to be cryptic to avoid burning bridges too soon, even ones unlikely to be crossed.

Re: The problem of fake numbers [Re: Magnetoman] #584973
02/11/15 5:05 am
02/11/15 5:05 am
Joined: Dec 2004
Posts: 9,332
Scotland
kommando Offline
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Turn up at one of the big auctions and offer to check for the buyers for a fee, any seller than refuses is not a lot to bid on. One trip required.

Re: The problem of fake numbers [Re: Magnetoman] #584977
02/11/15 5:17 am
02/11/15 5:17 am
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UK
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craig Offline
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there are processes already in place for this , but as soon as you ask if its ok to remove the powder coat or paint/enamel im sure youwill be told where to go , wasted trip , a lot of the stamp up obs are so bad a visual inspection is all that's req . if youve done your home work , after all that some of the new owners of these toys are not that interested as the amounts involved are small to some

Re: The problem of fake numbers [Re: Magnetoman] #584997
02/11/15 10:44 am
02/11/15 10:44 am
Joined: Mar 2005
Posts: 10,131
Boston, Massachusetts
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John Healy Offline
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Boston, Massachusetts
Quote:
a lot of the stamp up jobs are so bad a visual inspection is all that's req


And a lot are very, very good which is why they finally put the Logo behind the numbers. Of course that said, there are logo stamps about for the asking. And in reality the new raised number block on Triumph and BSA models actually made it easier to modify the numbers.

Quote:
after all that some of the new owners of these toys are not that interested as the amounts involved are small to some


OK Robin Hood, that is until it is your bike that is stolen or the money you lost because the bike you just bought turned out to have modified numbers.

My phone was a buzz after the two Vegas auction this year. Seems a lot of people brought bikes with questionable heritage to the auction. This seemed especially true for collectables like Triumph TT models.


Re: The problem of fake numbers [Re: Magnetoman] #585005
02/11/15 11:33 am
02/11/15 11:33 am
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Posts: 877
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Magnetoman,



Does the process work on powered-coated ferrous frames and alloy castings? If so, that is amazing and wish you a speedy review process with the patent office....

Re: The problem of fake numbers [Re: craig] #585007
02/11/15 11:36 am
02/11/15 11:36 am
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Magnetoman Online content OP

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Originally Posted By craig
there are processes already in place for this , but as soon as you ask if its ok to remove the powder coat or paint/enamel
That is why for it to be a useful development any new process has to be portable, non-destructive, and accurate.
Originally Posted By craig
after all that some of the new owners of these toys are not that interested as the amounts involved are small to some
Determining whether or not numbers are fake is a determination of fact. However, what people do with facts is much more complicated since it depends on human behavior. For example, some buyers are so wealthy that $30k may be irrelevant to them. Still, to the extent auctions are viewed as contests, eqos are involved in winning them. The amount spent to win may be irrelevant, but the blow to an ego in having it learned they were a sucker for buying a fake bike may not be.

Paying higher prices for matching numbers bikes is in one way irrational, in that the performance of a bike doesn't depend on the numbers stamped on it. Further, Lord Kelvin wrote that "Large increases in cost with questionable increases in performance can be tolerated only in race horses and women." Had he lived a century later he might have added "and TT Bonnevilles, and Rocket Gold Stars." Such desires have created a demand which unscrupulous people have been working to help fill. A portable, non-destructive way to detect fakes benefits everyone except the fakers.

Re: The problem of fake numbers [Re: kommando] #585010
02/11/15 11:52 am
02/11/15 11:52 am
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Originally Posted By kommando
Turn up at one of the big auctions and offer to check for the buyers for a fee, any seller than refuses is not a lot to bid on. One trip required.
Well, maybe, but. If someone shows up with a dowsing rod claiming to detect fake bikes, how many people are likely to pay, and how much? Even if they are inclined to believe a person has more to offer than a dowsing rod how many people would pay more than, say, $100? Also, twenty people might be planning to bid on a particular bike that the seller wants everyone to know is genuine, but only the seller would pay.

Anyway, if there were customers for 20 bikes, which seems pretty optimistic for the first time this were done, at $100 ea. that's $2000. Air fare, hotel, and local transportation would eat up a lot of that leaving a fairly low hourly rate for 2-3 days of effort. If money is to be made from this it seems like it will be with auctions for Bugattis not BSAs

Re: The problem of fake numbers [Re: Magnetoman] #585033
02/11/15 2:57 pm
02/11/15 2:57 pm
Joined: Oct 2006
Posts: 2,592
Elburn, Ill. USA
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Irish Swede Offline
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I would certainly be interested in any process that would expose faked numbers,
but I have learned that many fakes can be detected if the person viewing them
has taken the time to look at a lot of real numbers to study what the numerals
are supposed to look like, and how the real ones were stamped.

Two years ago, a very nice set of pre-unit Triumph cases appeared on eBay, with stamps indicating
the set was from a 1959 T120. What looked odd was that they were TOO perfectly stamped:
nice and straight, evenly spaced, and in line with the top of the case.

I have seen a lot of pre-unit cases, and several from '59 Bonnevilles,
and none of them looked like that. Then, last year, what was being passed as a "59 Bonneville"
appeared for sale on eBay. Guess what? Those same cases re-appeared, on that bike.

Fellow BritBike contributor "'59 Bonnie" exposed this fraud,
but I suppose some unknowing person bought the bike anyway.

Re: The problem of fake numbers [Re: Magnetoman] #585048
02/11/15 4:00 pm
02/11/15 4:00 pm
Joined: Mar 2002
Posts: 877
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rick e. Offline
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"Well, maybe, but. If someone shows up with a dowsing rod claiming to detect fake bikes, how many people are likely to pay, and how much? Even if they are inclined to believe a person has more to offer than a dowsing rod how many people would pay more than, say, $100? Also, twenty people might be planning to bid on a particular bike that the seller wants everyone to know is genuine, but only the seller would pay."

MM,

I see only two ways your 'acid test' would work.

1) A major auction would have to insist that ALL numbers be vetted by your method before being offered to the public. You get paid, auction house feels better, all buyers feel confident, costs get folded in total sales

or

2) Someone buys a $$$ item and then lets you verify it. If things go south, off to the court system

I for one, could not deal with seller(s) and buyer(s) directly pre-sale. When science is involved, things could get ugly...


"Back in the garage with my bullshit detector
Carbon monoxide making sure it's effective...
----THE CLASH-----

Re: The problem of fake numbers [Re: rick e.] #585057
02/11/15 4:32 pm
02/11/15 4:32 pm
Joined: Nov 2011
Posts: 4,432
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Magnetoman Online content OP

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Originally Posted By rick e.
1) A major auction would have to insist that ALL numbers be vetted by your method before being offered to the public.
That's not going to happen. Auction houses make their money from the number of items that go under the hammer and anything that keeps people from consigning items cuts directly into their income. For them to tell sellers all motorcycles were going to be screened for bogus numbers would clear the place out as fast as yelling "Immigration!" in the kitchen of any restaurant in the Southwest. As long as auction houses don't "know" there are such problems they can continue to pretend there aren't.

Originally Posted By rick e.
2) Someone buys a $$$ item and then lets you verify it. If things go south, off to the court system
Again, this points to Bugattis not BSAs being the market.

Originally Posted By rick e.
When science is involved, things could get ugly...
Um....

Re: The problem of fake numbers [Re: Magnetoman] #585091
02/11/15 6:56 pm
02/11/15 6:56 pm
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zoe Offline
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Years ago I bought a Yamaha DT1 that I was pretty sure was stolen because the engine number had been ground off. I got it very cheaply because of that and I took it to our local police station before I even brought it home. They put hydrochloric acid on the area where the numbers had been ground off and in a few minutes the original numbers began to appear, evidently due to the aluminum being more dense where the numbers had been stamped into the case. Fortunately there was no record of the bike being stolen so they let me take it home.

Re: The problem of fake numbers [Re: Magnetoman] #585096
02/11/15 7:16 pm
02/11/15 7:16 pm
Joined: Mar 2007
Posts: 1,153
Winona, MN
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I hate to be the fly in the ointment, but by offering the service of verifying stamped serial numbers, you are sticking your neck on the line. If for some reason a mistake is made, you could be held legally liable for the difference in sale price or appraised value.

In the art world, appraisers, gallery owners, curators and conservators are very, very, very cautious (and reluctant) when authenticating a work of art. If they state a work of art is original, and it is later proven a forgery, not only are their careers and reputations tarnished, they can be sued. There are more than 10,000 known fake works of the prolific 19th century painter Camille Corot. Most are obvious to the trained eye, but many fakes may hang in museums today.

I would never consider buying a valuable bike without unquestionable provenance and confirmation from the owners' clubs and factory dispatch records. Money does strange things to people and if it looks to good to be true, it probably is...


1966 Triton
1962 BSA DBD34 Gold Star
1966 Triumph Bonneville
Re: The problem of fake numbers [Re: Swan] #585107
02/11/15 8:06 pm
02/11/15 8:06 pm
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Magnetoman Online content OP

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Originally Posted By Swan
by offering the service of verifying stamped serial numbers, you are sticking your neck on the line. If for some reason a mistake is made, you could be held legally liable for the difference in sale price or appraised value.
I understand the issue you are raising. However, at least in my part of the country it's normal practice to hire an inspection service to prepare a report on problems with a house before an offer to buy takes effect. Irrespective of whether the inspector misses something important that later costs the buyer money to fix, or incorrectly points to something that actually isn't a problem that the current owner is forced to spend money addressing in order for the deal to go through, or even incorrectly points to something that results in the deal falling through, the wording of their contract protects them from both the buyer and the seller. A service to inspect a motorcycle would be more like this than that of verification of a one-of-a-kind fine art object.

Basically, for the reasons you give, a service would have to be offered as a "best effort" rather than a "guarantee." However, if it is someone knowledgeable who is hired to apply their best effort to prepare inspection reports on Gold Stars, Bonneville TTs, Black Shadows, etc., there are many cases every year where it would be money very well spent. As prices continue to rise one can expect the level of fraud to more than keep pace.

Re: The problem of fake numbers [Re: Magnetoman] #585141
02/12/15 12:29 am
02/12/15 12:29 am
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zoe Offline
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Magnetoman,

How about a brief up-date on the restoration of the first Spitfire Scrambler?

Re: The problem of fake numbers [Re: zoe] #585143
02/12/15 12:58 am
02/12/15 12:58 am
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Magnetoman Online content OP

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Originally Posted By zoe
How about a brief up-date on the restoration of the first Spitfire Scrambler?
The thread in the Projects forum contains all there is to tell. Slow though progress is, between it, fettling my new BB Gold Star, another restoration I haven't mentioned, travel to exotic locations, jet lag, and my real job, it's a miracle there's ever any progress at all. Finishing the gearbox is probably next, but it will be another week before I'll have free time so things might change by then.

Re: The problem of fake numbers [Re: Magnetoman] #585177
02/12/15 9:16 am
02/12/15 9:16 am
Joined: Oct 2006
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Elburn, Ill. USA
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Irish Swede Offline
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Ah, yes. Work is the curse of the motorcyclist class !

Re: The problem of fake numbers [Re: Magnetoman] #585225
02/12/15 3:00 pm
02/12/15 3:00 pm
Joined: Sep 2001
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Comox BC Canada
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Gordo in Comox Offline
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Very interesting thread. For me the originality issue is not something I really worry about, most likely because I do not feel it is worth the $$$ to get it. Some years ago on a bike trip we ran across a chap who was keen for us to see his Gold Star. When we viewed the machine in his shop we discovered a iron top end on BB34A cases in a BB31 bitsa frame. When this machine was bought by this owner the registration listed it as a GSA Gold Star. The local knowledge was that if a '34' was in the serial number it would be a Gold Star. Awesome.

When real GS bikse were new they were changed all the time to suit the owner. Even dealers would switch things around before bikes were sold. Engines ended up in different frames, frames were wrecked and replaced with B31 frames, engines were put into BB32R frames, engines were blown up and replaced. There was never any whining about originality. If the bike was a runner it was good enough and no one was re-stamping numbers to match the factory despatch numbers. About fifteen years ago a pal discovered that he had reunited a GS engine with the frame it had come to Canada in. This occurred what he bought a loose engine from a local guy to fit into a spare frame he had kicking around his shop. Just a nice tidbit about that bike.

Today I can point to my 53 5T and talk about how our neighbour bought it new, it is very original. My 38 Ariel that was owned by a friend of the family in the 1940s, maybe since new, has all the bits it came with according to the dating certificate I got from Dragonfly but these are only interesting bits in the overall conversation about these machines. They do not make the machines any better than machines with replacement parts.

So aside from the profit motive are there folks out there making 'fake' machines for bragging purposes? If so it would be the same as cheating at some sporting event then bragging about the ill gotten victory. Hollow bragging for sure.

Gordo



Without frequent roadside repairs there is no fun in riding!
Re: The problem of fake numbers [Re: Magnetoman] #585252
02/12/15 5:54 pm
02/12/15 5:54 pm
Joined: Dec 2011
Posts: 284
Norfolk England
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DBDBrian Offline
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Norfolk England
Yes two very interesting threads, How original is original?
When these things were being used as every day transport, (I used to ride my Goldstar to work everyday) or raced at the weekend, they were being constantly repaired.
In the early sixties I fitted a new set of genuine BSA crankcases, crankshaft, cylinder barrel, and internal parts, to a mates Goldstar after a conrod brakeage.
The only item that was distinguishable from the the original parts being the crankcase, as it had no numbers apart from the date stamped inside the timing chest. It was duly stamped up with the original numbers, using the only stamps available, but not exactly the same font as BSA had used. So now we have an engine with all these GENUINE new parts, with the crankcase being the only part evident as new due to the incorrect font.
Now where does this leave us, this machine still exists, so is it a genuine Goldstar or not?
The same situation would apply with a genuine new frame, as I cannot imagine that even dealers would have had the identical font stamps as BSA used.
I am not condoning a deliberate attempt to mislead, but I tend to think there is sometimes more to things than maybe apparent.
Brian


Brian

Made In England
Re: The problem of fake numbers [Re: DBDBrian] #585270
02/12/15 7:25 pm
02/12/15 7:25 pm
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Magnetoman Online content OP

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Originally Posted By DBDBrian
How original is original?
I'm reminded of the story of the museum that owns the actual axe George Washington used to chop down the cherry tree. Other than having had its handle replaced twice and its head once, it's completely original.

If it were somehow possible to do an experiment that completely removed money as a factor I strongly suspect most people given the choice between two otherwise identical machines would choose to own the matching numbers one. Even people who say it's irrelevant. There is a strong preference by a significant number of people for a machine that is "just like it came from the factory." And it counts in the minds of a significant number of people as "original" whether or not, like George's axe, it might have had its RRT2 gearbox replaced (but, by an authentic RRT2). Without getting into the psychology of what is behind this, or whether it is "reasonable," it is the reason such machines command higher prices.

Re: The problem of fake numbers [Re: Magnetoman] #585280
02/12/15 8:09 pm
02/12/15 8:09 pm
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Posts: 395
UK
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craig Offline
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I feel original is how it left the factory with all documentation , if you built a complete bike from original parts the old log book would clearly state "Built Up" I have one of these books , , is a restored bike original ? there is a growing number who say not and I agree with this line of thought , which makes a original unrestored bike very very rare , the machine you have maybe very nice but I would not count it as original and would expect the price to reflect this should it ever be for sale

Re: The problem of fake numbers [Re: Magnetoman] #585281
02/12/15 8:15 pm
02/12/15 8:15 pm
Joined: Sep 2013
Posts: 1,664
Pacific northwest
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quinten Offline
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Pacific northwest
From reading ...
The best , non invasive , way to check numbers appears to be with 'photoshop'
Take a series of macro shots with a variety of oblique light angles .
Use enlargement , brightness and contrast tools to bring out any shadows .

The best lightly invasive technique is to use various light acid washes on the numbers pad .
As the plastic impact zone underneath the visable stamp goes many times deeper than the visable stamp itself .

Numbers can be lifted even if the pad was filed or peened .
As long as there is ' some ' original invisible plactic zone grain distortion left , below any visable changes , an acid wash oxidises the metal grains at a different rate . The original numbers can shine through , like a ghost image in a double exposure .

Check out the photos in this forensic pdf www.intechopen.com/download/pdf/13406

.

Re: The problem of fake numbers [Re: Magnetoman] #585329
02/13/15 9:14 am
02/13/15 9:14 am
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Posts: 395
UK
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craig Offline
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UK
this is what you used to get with the old system if you built a bike from origional parts , interesting engine number , i have this bike and it is a swing arm 6t


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