Question: What is the ruling reading and downloading books from the internet with knowledge that its owners benefit from their sale?
Answer: “The one who spreads it on the internet and wants to spread it, and in most cases he does not spread it except he wants to benefit the people. As for the owners of publishing houses who do not want to spread it except the cover, in most cases, or they spread what they want to spread or benefit from. Whoever spreads his book in order for it to be benefited from, then it is allowed to benefit from it and for him is the reward with Allah and recompense if he seeks it from Allah. A question remains: is benefiting limited to reading only or selling? Whoever spreads his book in order to benefit without conditions nor does he restrict it, then it is allowed for the one who wants to read it or sell it to do so, except if he says this is for benefiting only.
We advise the one who Allah granted success to benefit the Muslims not to reserve [knowledge] and to spread knowledge to the best of his ability. Whoever Allah wants to benefit by him, He will benefit [others] by him and behind that for you is reward from Allah. And is knowledge spread except for benefit?…”
[Asilah Minl-Emaaraat found here: https://www.sh-yahia.net/show_sound_2594.html from 9:55 mark until 11:25]
Faisal bin Abdul Qaadir bin Hassan