Ruling on downloading e-books and making use of them
Question

Publishing houses write at the beginning of many of their books words to the effect of “No part of this book may be reproduced or photocopied without written permission from the publisher.” If I find these books published for free on the Internet, and available to anyone who wants to download them, is it permissible to download them and read them?
Praise be to Allah.There is nothing wrong with downloading e-books published on the Internet, or reading them, because one of the following two scenarios must apply to them:
The first scenario:
The book has been published with the permission of its author or copyright holder – which applies to many books, praise be to Allah – as the authors of these books and papers want to spread knowledge by electronic means, seeking reward with Allah, may He be exalted.
The second scenario:
The book has been published without the permission of the copyright holders, but the aim of downloading it and reading it is personal benefit, not commercial publication or to get hold of work done by others in order to alter it and claim it as one’s own work.
In that case, the author or publishing house has no right to prevent educated readers and seekers of knowledge from reading and downloading these books that have been published electronically.
What has been issued of statements by Fiqh Councils acknowledging copyright should be understood within the framework of regulating commercial benefits first and foremost and, secondly, preventing the mischief of plagiarism and forgery. It is not intended to completely forbid any form of benefitting from the books, to the extent that some of them regard merely quoting from a book or article and attributing it to the author as a transgression of copyright, unless one has obtained special permission beforehand for this exact quotation.
Shaykh Ibn ‘Uthaymin (may Allah have mercy on him) was asked about the ruling on photocopying books, and he replied:
What we think is that if it is for personal use, there is nothing wrong with it. But if it is for commercial gain, then it is not permissible, because it is detrimental to the publishers’ or authors’ interests."(Thamarat at-Tadwin  p.142).
He (may Allah have mercy on him) also said:
What I think is that if an individual makes a copy for himself only, there is nothing wrong with that. But if he makes copies in order to sell them, this is not permissible, because it is harming others, and it is akin to underselling a fellow Muslim, because if they are selling [a book] for one hundred [riyals], and you make copies and sell it for fifty, this is underselling your brother."(Liqa’ al-Bab al-Maftuh 178/19).
Here we are not trying to discuss this complicated issue in detail and list the different scholarly views regarding it in all circumstances and categories. Rather our aim here is to highlight that there is nothing wrong with the seeker of knowledge, educated person or researcher downloading books that he comes across on the Internet. But he should take care with quotations and attribute them to their sources, and he should not make any commercial gain as a result of downloading or publishing it, especially when the two types of reasons mentioned above are mingled in cyberspace, so no one has the right to prohibit what is in principle permissible on the basis of doubt or some unique circumstances.
Praise be to Allah, the academic and publishing markets have proven that e-publishing is a different market to paper publishing, and one of them does not cancel out the other; rather each of them has its own customers.
See also the answers to questions no. 116782 and 81614 .
And Allah knows best.