IIRC, "M-Disc" branded discs stopped being "M-Disc"-spec at some point, but since it's quite a niche product that peaked (over?) a decade ago, it's hard to find any definitive information about this in 2026. It's a shame because I liked the format. I'd be glad to see any form of confirmation or correction.
> Verbatim clarified that these discs were advancements. The technical changes resulted in a different appearance and the ability for higher burning speeds, the changed media-ID was due to an adaptation with regard to other Verbatim products. Verbatim had already shipped the first modified media in early 2022. The data security of the new discs is not inferior to that of the old discs: Data should also last 1000 years, according to the manufacturer.
Still using m-disc for family photo albums and having them in the bug out bag in case something goes wrong. Inexpensive and light. Such a shame the disk format is dying.
I agree, but it's worse than a shame: it's an indictment of the tech industry!
We have the entire planet storing all sorts of important business and personal data digitally - and no longer a good, common way to ensure it lasts even a decade.
If you buy fresh SSD/NAND media, treat it as write-once (or write to it just a few times) and fill up only a small-enough fraction of the logical space (so that the device can use pseudo-SLC "fast/caching" mode for the entirety of your data) the data on it ought to last a really long time. Especially if you avoid high temperatures during storage, and read it back every few years. Physical data remanence is much more of a concern for NAND that is nearly worn out.
> LTO tape exists and should last 30 to 50 years in good storage conditions.
Except tape is now rare-bird datacenter thing. Super expensive, and hard to find drives.
The nice thing about discs is they're a mass market consumer medium, so drives have (historically) been very readily available, and they typically have backwards compatibility with old formats.
The tapes? Yes. The hardware, though? I'm not sure I would bet on having compatible hardware to read a particular LTO generation tape, decades from now, given how specialty the hardware already is. I don't think there's any free lunch to be had here: the storage media needs to be viable, and you have to have a recovery strategy that's equally viable as well.
EDIT – that being said, "tape as a service" does exist... it's called S3 Glacier.
What are the threat models for tape, and how much do they vary for discs?
I assume if I leave either in my car in an Arizona summer day, it's toast. But are tapes more prone to mould damage in a damp climate, or media shedding if fed through a slightly out-of-adjustment drive?
The problem with M-disc was that it was always a sideshow on the mainstream optical disc market-- like LightScribe/LabelFlash, it was a feature most people weren't interested in except for possibly box-checking during purchase. The main audience was still people buying generic blank discs and burning single use discs or short-term backups.
There is/was an opportunity to box the product up with a clear marketing message of "here's a SMB-scale backup solution", something cheaper than tape, and more built-for-purpose than buying USB hard drives and dangling them off the back of a PC.
I'm picturing the M-disc technology but each disc is pre-installed in a cartridge to discourage accidental scratches/fingerprints/leaving surfaces directly exposed to the sun. It reinforces the "this is durable and you can probably put legal documents you might need for 5-10-20 years on it and leave it in a safe" story. This also creates a vendor-lockin product at a premium price, while quality conventional CD/DVD media was always competing with "but Fry's has spindles of 500 discs for $12.99!"
LTO is enterprise gear that is not suitable for people. If you want to waste alot of time with backups, curate your stuff and get it on optical media. Better yet, print the good stuff on archival papers and ink and stow them securely.
The older generations are pretty accessible price wise yes. They're pretty awful for home use though. Those tape drives are LOUD. Backing up my 90TB NAS takes a week. I don't want to sit in that squealing for a week in my flat. Restoring a single file is a PITA also.
I just use a box full of old harddrives now, i basically use those like tape cassettes.
> I just use a box full of old harddrives now, i basically use those like tape cassettes.
Re: hard drives – I gave up entirely on the idea of storing backups "at rest" indefinitely, and use two NASes at different sites. I only store ~50TB, and I plan to need to recover every five years (e.g. when a working computer finally gives up the ghost.) I end up replacing a HD in a ZFS pool once every two years.
LTO9 is like 45TB for <$100 (I got a bunch for €55 a piece), so 4.5TB for <$10 is being generous. And even if you didn't think they lasted 30-40 years and made copies every 3 years, it's still cheaper, not to mention you have fewer tapes to manage.
Also: I don't have a bd/dvd player in my house today, so even if there are the most tremendous gains in medical sciences I'm almost certainly not going to have one in 100+ years, so I'm not sure m disc even makes cost-sense for smaller volumes.
Maybe if you want to keep your data outside for sunshine like the author of the article, but that's not me...
> so even if there are the most tremendous gains in medical sciences I'm almost certainly not going to have one in 100+ years
Never say never. People of today are building "90s entertainment center" setups for nostalgia, complete with VCRs. Given how many generations of game consoles had DVD drives (or BD drives that supported DVDs) in them, I would fully expect the "retro gaming" market of 100 years from now to be offering devices that can play a DVD.
> Also: I don't have a bd/dvd player in my house today
You have just stumbled on the inherent problem with any archival media.
You really think you will have a working tape drive after 40 years?
Hell, in my experience tape drives are mechanically complex and full of super thin plastic wear surfaces. Do you really expect to have a working tape drive in 10 years?
As far as I can tell there is no good way to do long term static digital archives, And in the absence of that you have to depend on dynamic archives, transfer to new media every 5 years.
I think to have realistic long term static archives the best method is to only depend on the mark 1 eyeball. find your 100 best pictures, and print them out. identify important data and print it out. Stuff you want to leave to future generations, make sure it is in a form they can read.
I do think LTO is a common enough format, and explicitly designed to be backwards-compatible, that it is very likely to be around in 10 years. The companies that rely on it wouldn't invest in it if they didn't think the hardware would be available. 40 years, harder to say, but as someone who owns a fair bit of working tape equipment (cassette, VHS, DV) that is almost all 25+ years old, i wouldn't think it'd be impossible.
That said, i imagine optical drives will be much the same.
It is only backwards compatible two generations, occasionally something slips at the LTO trust (or wherever those things are designed) and you get three generations. But if I have a basement full of LTO1 tapes no currently manufactured drive will read them. I would have to buy a used drive and the drives were never really made all that well. Better than the DAT drives one company I worked for used for some of their backups. But still mechanically very complex with many many small delicate plastic parts that wear out quickly. Those DAT drives were super delicate and also suffered from the same generational problems LTO does. We had a bunch of DAT1 tapes somebody wanted data from but had no working drives to do so. All our working drives were newer DAT3 and 4
That was always the hard part to justifying tape backup. the storage is cheap. but the drives are very expensive. And never seemed to last as long as their price would warrant.
This has little to do with whether you curate. That's a whole different discussion about optimizing for cost, where many many terabytes eventually make LTO become cheaper. When we're specifically looking at reliability for important files, there might only be one tape's worth of data. It's a $3000 fee to make that tape (and its backups) last a long time in storage, and having more or less data barely affects the price.
You presume the things I want to save aren't individually TiBs in size.
Anyone who has even an amateur interest in, say, making movies, probably has at least a few projects worth of 4K RAW footage they would hope outlives them. (And the average small-time YouTube content creator has far more.)
I don't know, i don't think any one after me is gonna scrounge through hours of raw footage of an old project of some grandparent (me). Not that I have kids but anyway.
If anything I doubt they'll bother looking at the final cut.
It would be neat if someone resurrected Iomega and launched the 2026 version of the Zip drive for local backup. It'd be something like $200 (same as the original Zip drive) and it would take 20TB WORM tapes that cost $20 each. There would be some kind of horrible limitation, like it would take 2 months 24/7 to actually write 20TB, but it would come with simple software that rapaciously grabbed your whole cloud life and local data, and the tapes would last forever.
I just looked, and iomega.com seems to be some kind of malware site. Sad.
LTO drives are expensive but they are very well designed and it is the most reliable portable storage format available. Full LTO tapes in a good fire rated safe really provide a fantastic sense of security. The cost of the drive is amortized over the total bytes you store.
Those tapes in a fire rated safe give a sense of security before the fire.
After the fire, it is likely that the tapes and the papers in the safe are a pile of ash. Fire-rated safes often don't survive fires especially if you live in wildfire country.
Assuming you need to “get up and go”, like a refugee situation, what are the chances that you’ll find a drive that can read Blu-ray disks, versus the chances that you’ll find a LTO tape drive ?
Blu-ray drives are fast becoming hard to find, so I'd pack a USB bluray drive with your discs.
New computers don't have them and haven't for a few years. I purchased a drive recently and to get a quality drive, I had to go for a NOS pioneer drive, or get another LG, and the LG drives are kid-of shit.
How exactly are they becoming hard to find? There's literally tens of options for brand new drives I can order for next day delivery on Amazon, and endless choice of second hand options on eBay.
For DVDs: Walmart still sells a USB reader/burner for $30. Also I'd bet something will be able to read recordable disks in the future even without drives. Maybe a super super high resolution (compared to now) picture can simply be used to get the data from it visually in 30-40 years.
The disc reader on consoles is optional these days. Nowadays many are opting for digital only variants. It's likely those will be the only option in ~10 years, or they'll switch to flash key cards (like the Switch) just to appease retailers.
>>The disc reader on consoles is optional these days
You can't buy an Xbox Series X without a BD drive. PS5 exists in both variants, but it's not like you can only buy a disc less PS5 and then you have to buy a drive extra.
I still use optical discs for my personal backups and have done since 95. My biggest concern is whether I will still be able to buy new drives and blank media in 10, 20 years. Or physical media at all...
Please do not say LTO tapes. The drives are huge, noisy, expensive, and they have a very quick deprecation policy (new drives cant use old tapes).
I’m in a similar boat. The USB to SATA adapter has kept my 5.25” drive going for quite a few years.
Some of my discs are hitting a decade and I am about to create a new set of backups. The market is smaller but the portable blu ray drives are becoming the default now.
So far I’ve just kept extra discs on hand plus a backup portable drive. Hopefully blu ray discs will manage to stick around as long as writable dvds.
You can still buy brand new LTO-4 and up from a brief search - I think due to the enterprise use cases it’ll hang around longer than any other format. Tape existed before the HDD; it’ll be there watching HDDS pass away into the ether too. Probably a few tape drives on the Starship Enterprise somewhere.
More seriously; you can buy used lto-7/8 for very little these days, and the tapes are extremely cheap per gb. The drives are somewhat loud; it’s not a beside device for sure. I’m finding it a bit of a pain to manage a good backup strategy with them.
- You suggest buying multidecade old drives that are no longer manufactured, have weird interfaces that your 2026 PC no longer has, are expensive, large, noisy
- You then mention LTO7 which will not read your LTO4 tapes and is not just expensive but literally out of reach economically for single home
Basically LTO is a terrible backup strategy unless you have a lot of money regularly that you will spend in order to upgrade your entire equipment every two/three generations (otherwise your newer equipment wont read your old tapes). Or you have so much data to backup that cost of drives is not really an issue.
Using HDDs for backup is also a terrible long term strategy, because you must have a lot of money regularly, to buy new HDDs to replace your old HDDs and this much more often than you need to buy a tape drive to migrate your tapes.
I have stored a lot of data on HDDs, and the only reason why I have not lost any of it yet is because I have always used duplicate HDDs. After 5 years or more, most HDDs had some corrupted sectors, but they were not in the same positions in the duplicate HDDs, allowing complete recovery of the data.
The reality is that both tapes and HDDs suck. What is really needed for long-term storage is a write-once memory with a lifetime of 100 years or more, based on an open standard that would ensure the availability of readers in the future.
If such a memory would use optical reading, it would have to use a great number of layers, filling a 3D volume, in order to achieve densities comparable with the magnetic media. While several research projects in this direction have been announced from time to time, until now none of them has resulted in a commercial product.
I'm confused - I and many others basically have these cobbled together LTO setups. I'm only "Prepping" by finally moving some of my backups away from home, so in case of a fire or whatever I'm not out of luck. You could cobble one together now for anything from OG DAT tape to LTO-10 for ~10K, if you need. So big fire happens, you file an insurance claim, and as part of the payout buy whatever setup you need, or hire some specialists. Once we are at LTO-20, there's no reason to assume LTO-10 and older drives are totally gone from the used market?
I'm not preparing for some asteroid impact level event, in that case the loss of my backups will presumably not really matter all that much.
That’s babble to 80% of the nerdy HN audience. “Copy your stuff to this usb drive and keep it somewhere you aren’t” is easy for almost anyone to comprehend, accessible but operationally difficult.
Maybe you're having issues with their writing style or something but the tech is simple. They copy their stuff to a tape and keep it somewhere they aren't. If a disaster happens they'll buy a new tape drive.
I'm not going to actually suggest LTO-7, but what do you think is a reasonable per-month cost for backing up your important data? If it's in the $5-$10 range then you can afford a $600 drive and some tapes.
> Basically LTO is a terrible backup strategy unless you have a lot of money regularly that you will spend in order to upgrade your entire equipment every two/three generations (otherwise your newer equipment wont read your old tapes).
"regularly" can be 10 years. Your new equipment doesn't need to read your old tapes. If you advance by 4 generations, you can buy 1 new tape to replace 10 old tapes. And the newer generations have abandoned that feature anyway.
I bought a thunderbolt to FC adapter; works perfectly on Mac and Linux.
I mention LTO 4 because you can today, buy multi decades old LTO-4. Brand new. So in multiple decades from now, I assume you’ll be able to find LTO-7 or 8; brand new. A drive might cost a little more to obtain, but given the plethora of used multi decades old lto currently out there, it seems reasonable to expect that in a recovery scenario you’ll be able to shell out for the right drive.
But yes for most HDDs or the cloud are better. No need to get spicy about it.
AFAIK the tapes are cheap, but tape libs aren't. Considering that they also take up a significant amount of space, I personally don't see them as a viable backup medium for most private users.
You don't necessarily need a lib, though. Especially if you're interested in a use case where you can store data in a go bag, safe deposit box, etc., it seems like having individual tapes would be preferable.
Individual used drives aren't too expensive (or at least didn't used to be). Libraries, in contrast, do tend to be more expensive (and also a lot more trouble to ship).
Which is disgrace when you consider that no optical drive is yet available that will not read original red book cd roms from the 80s.
You say "it can read from one generation ago" as if it was some great thing about LTO when it is just a laughably fast obsolescence policy and what really kills it for a home user.
A blueray drive manufactured today can still fscking write to a 90s CD-R from way before LTO even existed.
That is easy for optical drives, because there is no direct relationship between the size of bits on the optical track and the dimensions of the read/write laser head.
For magnetic media, the gaps in the magnetic circuit of the read/write heads are optimized for a certain dimension of the bits from the tape material and the efficiency of the read/write process greatly diminishes for other bit sizes.
So there is no obsolescence policy, but there is a real technical difficulty in ensuring compatibility with older magnetic media with different bit densities.
That is not that simple. There is a relationship between laser and media, most optical drives to this day have entirely separate lasers for different generations of media. At the very least, red vs blue lasers.
It is not as simple as claiming that optical drives have it easier technologically. If anything, I would claim that tapes have it simpler, definitely for reading at least. There is _nothing_ preventing LTO from retrocompatibility other than market forces.
Most optical discs do not have any guarantees about lifetime and the worst of them may survive only a few years.
There have existed special quality optical discs with gold mirrors that were guaranteed for 100 years, but those are no longer produced and a single modern tape cartridge stores as much data as thousands of those discs.
There are several mechanisms of degradation of optical discs. If the plastic does not seal well enough the metallic mirror, the metal can become oxidized and transparent, so it no longer reflects enough of the laser light. This is why certain archival discs used gold mirrors, which cannot oxidize. The plastic resin may also degrade in various ways and cause disc deformation.
The CD-Rs had an active organic layer that oxidizes, even if the mirror is gold. Some kind of rewritables weren't organic as far as I remember.
Also CD-Rs have the active layer (top) exposed to the air, but that was solved with DVDs which are a sandwich (which though caused its own issues with shearing)
Any guarantee made by manufacturer about data on tape longevity is irrelevant unless it is easy for user to create the storage conditions under which is warranted, and that is usually not cheap.
not hard to find stories about data on LTO tapes being unreadable after 5 years. The same as stories of data on even the worst CD-Rs being still readable after 30 years ( i can personaly attest to that).
Some CD-Rs will certainly be readable after 30 years, but there have been plenty of bad CD-Rs that have become unreadable after less than 10 years.
I had several hundred CD-Rs. Most of them were OK, especially the gold archival CD-Rs from Kodak, so I have migrated the data from them mostly to save space and improve access speed, not for them being too old. Nevertheless there have been a few that have gone bad, but I had duplicates for all of them, so I did not lose the data. Had I not been cautious, I would have lost some of the data.
The main problem of optical discs is their much too low capacity in comparison with magnetic media. A small suitcase with tape cartridges contains as much data as a big cabinet full of the most dense optical discs.
I believe they are all 5.25in, some are just in a case. Even the library drives are just two 5.25 bays put together, a full height drive; vs. the much more common half height.
This is true - I got a fiber channel LTO-8 FH drive off ebay brand new in the IBM packaging for less than 750$ Tapes are 60; so breaking even against 15$ per TB HDDs is pretty fast.
No, they are not. Specially when you have to find the one drive that will read your tapes , connect to your computer, and many other constraints that a user will have.
The connection to a computer does not have any special challenges, except that the computer must be a desktop with a free PCIe slot.
Unless you have a server motherboard with an on-board SAS controller, you need to buy a SAS HBA card, put it in your desktop and also buy a compatible SAS cable, in order to connect an LTO tape drive to the computer.
New tape drives are extremely expensive, e.g. $4500 for the last generation of LTO-9 tapes (18 TB/cartridge), but if you store at least a few hundred TB of data you recover the cost of the drive from the cost difference between HDDs and tape cartridges.
I have an older LTO-7 (6 TB/cartridge) tabletop drive, which has cost me $3000 about 7 or 8 years ago (new), and there are several years since I have recovered its cost.
If you do not intend to store more than 100 TB, the cheapest solution is to buy external HDDs, but for long term storage you must plan to migrate the data periodically, as the lifetime of HDDs is hard to predict and unlikely to be much greater than 5 years.
I specifically said do not mention LTO because I knew it would happen. LTO-advocates fail to see how pointless LTO is for someone who is well-served by a backup/archival strategy that uses optical media.
When I say "I'm concerned about whether I could buy newly manufactured drives and media in 10,20 years", the answer cannot possibly be "LTO". Because in order for LTO to make any economical sense, I would have to buy ancient LTO drives, and ancient LTO media compatible with those drives, and ancient computers compatible with the interfaces used by those drives.
Therefore I already know the answer on whether I could possibly buy newly manufactured LTO drives and media in 10,20 years, and it starts with a NO. Even today I would be forced to buy second-hand drives. Why would I even entertain LTO as an option, then?
Compare this to BD where in at least today you can buy a simple and cheap USB drive and new media, all of them manufactured today, and not break the bank while doing so. And drives have evolved from $propietary->PATA->SATA->USB, keeping up with the times and interfaces. (Interestingly, I can also buy newly manufactured USB 3.5inch floppy drives. But not media.)
I mean, certainly LTO has its advantages, but in the same way that someone requiring to archive 8TB of data would likely screech if asked to do so with BD media, it just doesn't make sense to suggest LTO as a long-term alternative here.
Really the one thing that's guaranteed to be manufactured in N years is _some kind of storage_. I wouldn't buy LTO-1 now, but later gens are going to be around for some time, just like CD-ROMs and other optical media, in some form. And readers will always exist barring an asteroid impact or whatever.
>Therefore I already know the answer on whether I could possibly buy newly manufactured LTO drives and media in 10,20 years, and it starts with a NO. Even today I would be forced to buy second-hand drives. Why would I even entertain LTO as an option, then?
This is just yet another example of a pointless argument, exactly as I mentioned. Why should I even care that you can scavenge for ancient stock (even if NOS), when my current concern is about something that is still manufactured _today_ ?
I know for sure optical media & DRIVES will still be available to purchase _brand new_ during the N years they're still manufactured, but also the M years that will follow where I will be able to find new/old stock after they stop manufacturing.
Period N by itself I expect is going to be somewhat long (see 3.5inch floppies), during which one can even expect to see drives with never interfaces (e.g. USB-C). Yes, I have no clue how long it is really going to be, and my concern is whether it will even last this decade.
OTOH I know 100% for sure period N is going to be effectively 0 for any LTO generation I could possibly buy. By the time LTO prices drop for some generation, it is because that generation is dead in the water.
And period M? It is going to incredibly long for optical due to popularity alone, much longer than _any generation_ of LTO could ever hope to be.
And if you say "well, certainly some form of LTO is going to be manufactured in 20 years from now": it should be obvious that I couldn't care less, unless that form of LTO would be able to read the tapes from any generation I can possibly buy now.
The fact that LTO-21 will still be manufactured is of absolutely no relief to someone with LTO-4 tapes. In fact, for all I'm concerned, it could very well be an entirely different media type only sharing the first three letters of the name.
These are not arguments in favor of LTO. If you're already assuming that if your LTO drive breaks you either scavenge for another or basically assume the loss and buy all new media from newer generation and repeat... what's the point of LTO then? Why not buy SmartMedia cards (to say the worst thing that comes to mind)? I'm sure you can scavenge readers and media, and probably will have an easier time finding and using them than with any specific LTO generation.
In the meanwhile, let me keep burning toasters; at least there is a small chance I may be able to buy new drives 20 years from now, using whatever interface replaces USB-C, and they will still be able to read my current discs.
I mean you said it yourself: if you have terabytes of data, BD isn't practical.
I feel like this is all just two totally separate use cases. Nobody wants to burn 20-40 BDs per TB, just like nobody wants to use a tape drive (or maintain a RAID array, or whatever else) to back up 500GBs of family photos and tax documents or whatever.
At some point the volume of data dictates what solutions are practical.
I have a Verbatim BDR that was branded M-DISC. I burned a bunch of data and put a file full of hashes for the files on it when I started using BDR's as backups to get a feel for when my data might be at risk. I use it as a coaster on my desk. My kids have carried it around with sticky fingers. I fidget with it and flex it a good bit. I've left it on my patio table outside for months at a time. I wash it in the sink with dish soap from time to time to clean it and dry it with whatever hand towel is in the bathroom. I abuse it to see when it starts to lose data.
I've been doing this now for a bit over a decade. It hasn't experienced any noticeable corruption yet on ~22GB of data, but I'm not doing any deeper reads on it. Spot checks on my properly stored discs have also not lost any data.
The "killer" feature is actually that it was rendering traditional websites NOT fine, but in a bunch of hacks that would force a specific viewport width where most websites would render with reasonable font sizes and double tap to zoom to paragraph would fix the remainder.
Specifically this "killer" feature would already break traditional HTML pages with just text (that were 100% responsive even before "responsive" was a thing).
The entire mobile HTML stacks is hack on top of hacks. Like everything else in computing, TBH...
Cool, but the method of verifying the data (playing back the movie) seems non-optimal. The movie could have had some data corruption that went unnoticed.
Ideally the test should include the number of bit errors that were corrected using on-disc ECC. This could then also be used to estimate disc lifetime (preferably using multiple samples).
If you are willing to sacrifice some storage space on the disk, then dvdisaster (https://en.wikipedia.org/wiki/Dvdisaster) can add extra ECC data to the disk that will allow recovery even if some percentage of the disk errors out upon read later.
Granted, if one no longer has the mechanical drive, or if the disk errors out beyond the threshold where the extra ECC can correct the errors, the data's still lost. But it (dvdisaster) does provide some protection from the "bit-rot" case where the disk slowly degrades.
For this purpose, I think it would be nice to access the raw data, to see any errors that would be otherwise masked. As someone in the comments suggested, one might compare number of corrected errors in 1, 2, 5 years and compare to the number of redundant bits stored to estimate the expected longevity of the medium
Also, the storing it outside isn't a very good test of how long it will last inside.
Also also, M-Disc is like Imax, a theater could have that label because it projects 70mm film into a dome or because it's a regular movie theater with a lower resolution than your phone screen that licenses the rights to the name. There are M-Disc DVDs that use a special archival technology that requires compatible drives, but the M-Disc Blu-Ray discs are made with regular Blu-Ray manufacturing technology. With both Imax and M-Disc, they require a minimum quality level to license the trademark, but exceeding that quality level is far from exclusive to that trademark.
My understanding is that the thing that makes M-Disc DVDs special is that they don't use organic dyes in the recording. Blu-ray discs, with the exception of the weird LTH ones, by default don't use organic dyes. Consequently, the main magic of DVD M-Disc is just the default with BDR.
For a long time the vast majority of DVD-R disks have been light-to-dark (ie, the laser writing to a spot makes that spot darker, not lighter.) Dark-to-light disks were rare, the cheapest, and fell out of production pretty fast.
As tested, it doesn't matter because the disc didn't even have a UV safe resin. The lifespan of the data area is only meaningful if the rest of the disc is intact.
Granted, archival discs aren't designed for full-sun exposure to start with, so in theory, the failed disc could have outlasted the other under real-world archival conditions, and this test wouldn't reveal that.
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