[pdurrant]

Originally Posted by HarryT

There's clearly a whole continuum of different actions we could be talking about here. Lending my friend Joe a Kindle with a single book on it for a few days isn't the same thing as giving Joe a Kindle for his permanent use with access to my entire ebook library, and that in turn isn't the same as giving Kindles to half a dozen different friends or relatives.

I asked Amazon about this most explicitly back in 2012:

Thank you for your response to my question, but it seems to be a technical rather than legal answer to my question. Obviously no-one is able read my books (the DRMed ones, anyway) unless they have access to a device registered to my account.

But I am asking about the licence terms, and what they allow me to do, not the technical limitations imposed by the DRM system.

May I let my spouse read ebooks that I have bought (on a device registered to my Kindle Account)?
May I let my children read ebooks that I have bought (on a device registered to my Kindle Account)?
May I let a close friend read ebooks that I have bought (on a device registered to my Kindle Account)?

I'm sorry to go on about this, but I do want to understand how many copies of an ebook you expect a household to buy if everyone in the household wants to read it. Your licence terms seem to imply that a copy needs to be bought for everyone who wants to read the ebook.

To which they gave this reply:

I am sorry about the confusion caused by my colleagues reply to your query.

In this case, I can confirm that in most cases, Paid Books have on average 6 Licenses and Free books have on average 99 Licenses.

Publishers choose whether they apply digital rights management software (DRM) to their content. There is no limit on the number of times a title can be downloaded to a registered Kindle device or Kindle-compatible device running a Kindle application, but there may be limits on the number of Kindle devices and applications (usually 6) that can simultaneously use a single book. If the limit is less than six Kindles devices or applications for a specific title, you'll see the message "Simultaneous Device usage: Up to X simultaneous devices, per publisher limits" on the website detail page.

This means that your Spouse's, Children's and even your friend's Kindle can be registered to your account and can download and read your books from you Archived items. Provided they do not exceed the limit of licenses.

Therefore, you can buy one copy of a book and have it available to be read on up to six devices (if it is a paid book) and up to 99 devices if it is a free book.

In terms of use, you have purchase a copy of a book with us, and it is your copy. You may authorize any one you wish to read it, but that person's device must be registered to your account to do so.

This wasn't a response from first-line technical support. This was a considered reply from Amazon.

Amazon have licensing terms. I asked them about those terms, and they told me how they interpreted them. "You may authorize any one you wish to read it, but that person's device must be registered to your account to do so." That's good enough for me.