The provisions in Part VB usually only allow you to copy 10% or 1 chapter of something like a book. You can copy more than this if copies of the book aren’t available in a reasonable time at an ordinary commercial price.

In many cases, different editions of a book such as a textbook are quite different, so in copyright terms would be different “works”. Publishers don’t usually keep older editions available, so in most cases you will be able to copy more than the usual 10% or one chapter of these older editions – even all of it if you need it for your institution’s “educational purposes”.

So, to work out how much of a particular edition you can copy, there are really two things you’ll need to check on: are there real differences between the edition you want and the edition that’s now available?; and, is the old edition now unavailable (other than second hand)?