Hello:

I have suggestion for a DRM system that should make life easy and wondered what opions everyone else would have of it...

Peanutpress (now eReader i Think) had a DRM idea, whereby any bought book was encrypted with your credit card number - so to open the book you needed the credit card number. So - thoretically I could lend the book to my best mates, if I trusted them enough with my credit card number....
This idea was flawed however - all you have to do is change credit card, making the old number obsolete and therefore no problem to give to anyone / everyone.

My idea has come form this - which is to encrypt the book, but not tie it to any device in particular, any device with the software can read it, no password to open, it is easy to copy and even post on the internet if you want.
However the document could be encrypted with some kind of identifier which identifies who bought the original - thus pointing the finger, when a thousand copies are found all over the internet for 'free' download.

I could even lend them to my mates - as that would result in only 2 or 3 ( :( for example) copies of the original. Which can be easily identified as 'fair use'

It sounds good in theory. The problem is to guarantee that the original buyer is legit. What do you do with those who use stolen credit cards to make online purchases? They couldn't care less about pointing the finger, and a single stolen e-book can still spread like wildfire.

Won't work.

1. The real purpose of DRM is to restrict competition by locking the content to a certain reader. So the "content cartel" won't go for anything that will run on all devices/readers.

2. If you have the cyphertext and the key, getting the plaintext is now trivial - and the DRM has failed in its stated purpose.

And one more thing: making 2-3 copies for your friends is not, nor has it ever been, "fair use."

This is standard encryption with private and public key. It is just called authentication when using the private key to encrypt. The main problem is that you can decrypt with the public key and then use the decrypted content which is now without any way to identify the source.

And one more thing: making 2-3 copies for your friends is not, nor has it ever been, "fair use."

Perhaps the word 'Fair use.' were not the best to use and they are certainly not legally correct as the copyright in most books clearly states that unauthorised lending (amongst other things) is prohibited.
However, the main point is - a few years ago I went to a book signing by quite a well known author of Sci-Fi, he was more than happy to hear from me that the 'unauthorised' lending of one of his books, had resulted in my brother in law, buying his entire published works, and recommending them to his friends...

Perhaps the word 'Fair use.' were not the best to use and they are certainly not legally correct as the copyright in most books clearly states that unauthorised lending (amongst other things) is prohibited.

I'm confused here since we see to be jumping topics.

First, let's get this concept of "unauthorised lending" out. To the best of my knowledge, there is no such thing. The author/publisher/retailer has no authority whatsoever to tell me who can can/can't loan my paper books to. If they want to take me to court for loaning my computer books out at work, they can try - but I will win and win big. What I do with my property is my business.

The only right that the author/publisher has once the book has been published is copyright - which as the name implies, only impacts the making of copies of the book or the contents of the book.

"Fair use" is about the exceptions to "no copy" rule, allowing people to make, under certain conditions, copies of the content of the book.

However, the main point is - a few years ago I went to a book signing by quite a well known author of Sci-Fi, he was more than happy to hear from me that the 'unauthorised' lending of one of his books, had resulted in my brother in law, buying his entire published works, and recommending them to his friends...

Yeah, that's not so much "fair use" as much as it is "promotional losses," in other words, depending on essentially free samples to bring in more sales that offset the cost of the sample. That's a traditional marketing tactic in print literature, and there's no reason it can't be as effective a tactic with e-books.

Mind you, this only works when the cost of the book is low enough to encourage people to buy to support the author, instead of being so high that people want to steal it to spite the author. No DRM required.

...However the document could be encrypted with some kind of identifier which identifies who bought the original - thus pointing the finger, when a thousand copies are found all over the internet for 'free' download.

I could even lend them to my mates - as that would result in only 2 or 3 ( :( for example) copies of the original...

But what if just one of your friends passes it along to someone who is not so trustworthy? It gets broadcast and you get fingered!