“Lending is included in the purchase, but permanent sharing is not included in the purchase.”
TY. So you’re *assuming* it is excluded by the contractual terms of purchase.
1. Why are you assuming the seller imposes that unwritten term if copyright law does not provide such protection? Do you make the same assumption regarding a non-Jewish published recipe book?
2. How can the seller impose a term of sale that was never agreed to by the buyer? (Especially, considering, that the author published it through a publishing company which sold it to a retailer which resold it to the final consumer. How did any alleged unwritten [non-legally protected], non-explicitly agreed to, term carry over through all those channels? Do you assert such a term would even apply to someone who borrowed the book from the library or a friend or found a discarded copy of it? How so?)
3. Even assuming you to be correct, a violation of the contractual terms of sale merely give the original owner the halachic recourse to nullify the original sale/contract, demand the return of the book and at the same time refund the buyer the original payment for the book – thus reversing the original sales contract that was breached. After that the breach has been corrected and all parties are whole.