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How Dropbox Knows When You’re Sharing Copyrighted Stuff

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11–20 of 69 posts

Re: How Dropbox Knows When You’re Sharing Copyrighted Stuff

#11
Yet another reason not to use cloud services. For start dropbox is infrastructure provider and they have no right to snoop inside your files. If they start blocking stuff at their own will they are judge and executor.

Secondly there is lot of potential for abuse. Hacker could sneak hash collision into their database and essentially censor-ship any document he wants.

And finally I do not understand why there has to be protection from working with copyrighted stuff. Most of work I created is copyrighted, nearly every open-source product have copyright.

Even if there would be a movie there, it does not strictly mean it is illegal. Most people have right to create backups of their DVDs. Many jurisdictions allow to create copy for personal use and so on.

Re: How Dropbox Knows When You’re Sharing Copyrighted Stuff

#12
Almost all the recent news and tweets sidestep around the main question, which should be answered in a FAQ somewhere:

If I have copyrighted data on my Dropbox folder, and the system detects it, what happens? If I sync the copyrighted data with several of my computers, does that count as sharing?

Yes, I know what hashing is and yes, it seems the original reporter of the DMCA may have shared the file link through email or a website. Still, I need assurance that my data (including the copyrighted ones) will be backed up at Dropbox and available for my use at my leisure, indefinitely -- provided I don't "share" them in any public way.

Side note: all of my data on Dropbox is encrypted by a separate system, so it's unlikely that I'll be affected, but I still am interested in the issue.

Re: How Dropbox Knows When You’re Sharing Copyrighted Stuff

#14

> Dropbox checks the hash of a shared file against a banned list, and blocks the share if there’s a match. Encoding an mp3 is not a deterministic process. So if multiple people start with the same .wav file ripped from a CD (which itself may introduce errors) and then downcode it, they will end up with files which sound the same but are slightly different (and therefore hash differently). So, it should be straightfor…

That brings up an interesting question. At what point does a modified file no longer fall under copyright? If I had a copyrighted ebook and changed a single "o" to "0" I bet I could still be busted for distributing it (although it appears Dropbox would no longer automatically catch me). But what if I changed every single "o" to a "0"? Re-arranged words? Chapters? Upcased every lowercase letter? My guess is that's it'…

It would fall under the same rules as fair use. If the modified file is close enough to the original that it could deprive the creator of a sale, then it is certainly infringement. If you made it so different that it would not deprive the creator of a sale (for example, if you re-arranged every single word so that the words in the book were in an entirely random order), that would most likely be fair use.

Re: How Dropbox Knows When You’re Sharing Copyrighted Stuff

#15

> Dropbox checks the hash of a shared file against a banned list, and blocks the share if there’s a match. Encoding an mp3 is not a deterministic process. So if multiple people start with the same .wav file ripped from a CD (which itself may introduce errors) and then downcode it, they will end up with files which sound the same but are slightly different (and therefore hash differently). So, it should be straightfor…

That brings up an interesting question. At what point does a modified file no longer fall under copyright? If I had a copyrighted ebook and changed a single "o" to "0" I bet I could still be busted for distributing it (although it appears Dropbox would no longer automatically catch me). But what if I changed every single "o" to a "0"? Re-arranged words? Chapters? Upcased every lowercase letter? My guess is that's it'…

It's an interesting philosophical question, but intent is something that judges are much better at deciding than computer programs. And laws are generally written to be executed by judges (or, by extension, the threat of litigation).

Fun to think about, though. Especially if you start thinking about writing alternate endings, etc.

Re: How Dropbox Knows When You’re Sharing Copyrighted Stuff

#16
post #3

Dropbox certainly has a very dedicated advocate in Techcrunch. I wonder why.

I thought the same. It reads like a well crafted press release. It's factually accurate and fair game, sure, yet it doesn't sit quite right with me.

Re: How Dropbox Knows When You’re Sharing Copyrighted Stuff

#17
post #7

They use the same logic to save time when uploading a file that has already been uploaded by another user. Check hash of large file, see if it is already on the server and then just link it to your account.

I believe they stopped doing multi-user deduplication a while ago.

Re: How Dropbox Knows When You’re Sharing Copyrighted Stuff

#19

> Dropbox checks the hash of a shared file against a banned list, and blocks the share if there’s a match. Encoding an mp3 is not a deterministic process. So if multiple people start with the same .wav file ripped from a CD (which itself may introduce errors) and then downcode it, they will end up with files which sound the same but are slightly different (and therefore hash differently). So, it should be straightfor…

That brings up an interesting question. At what point does a modified file no longer fall under copyright? If I had a copyrighted ebook and changed a single "o" to "0" I bet I could still be busted for distributing it (although it appears Dropbox would no longer automatically catch me). But what if I changed every single "o" to a "0"? Re-arranged words? Chapters? Upcased every lowercase letter? My guess is that's it'…

It gets even more interesting if you use right to "quote" small parts of books.

Re: How Dropbox Knows When You’re Sharing Copyrighted Stuff

#20
Maybe I'm being daft here, but why don't would-be file-sharers just encrypt files and send their friends passwords along with the links? Neither the provider nor the copyright holders would be able to tell who was sharing what, unless they monitored IM, email etc..

Of course it does seem that anyone can abuse the DMCA with impunity, so strictly speaking this wouldn't stop the "notice and takedown" actions. It would however prevent the automated detection and might increase cost and difficulty for copyright complainers.

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