can you copyright some one else written work . and just add the sources. how much of your book can be claimed as yours if you use 50% AI generated content 25% open source or other sources. To answer directly: You can only claim copyright over the exact portion that you originally wrote yourself. In the scenario you described, assuming the remaining 25% is your original writing, you would only own the copyright to that 25% of the book. Here is exactly how the U.S. Copyright Office views a book with this kind of breakdown: 1. The 50% AI-Generated Content You cannot claim copyright over this portion. The U.S. Copyright Office has been incredibly clear on this rule: copyright protection requires human authorship. Raw text generated by an AI belongs to the public domain. This means anyone else can take that 50% of your book and use it, copy it, or sell it themselves, and you cannot legally stop them. When you register a book for copyright, you are legally required to disclose the presence of AI-generated material. The Copyright Office will explicitly exclude the AI-generated portions from your copyright claim. The Nuance: If you use AI simply for brainstorming, or if you extensively edit and rewrite the AI output to the point where it becomes your own original expression, you can claim the final edited text. However, simply writing a detailed prompt does not make you the author of the output. 2. The 25% Open Source or "Other" Content You cannot claim copyright over this portion either. Public Domain / Open License: If the material is completely free to use (like a work in the public domain or under a permissive Creative Commons license), you have the right to include it in your book. However, you do not gain ownership of those words just by putting them in your book. They remain free for everyone else to use. Other Copyrighted Sources: As mentioned in the previous answer, if this 25% belongs to another author who hasn't given you explicit permission, simply citing them does not protect you. That portion would be considered copyright infringement. 3. The Remaining 25% (Your Original Work) This is the only part you own. You hold the exclusive copyright to the specific words, thoughts, and expressions that you created yourself. You would also hold a thin copyright over the compilation—meaning the specific way you selected, structured, and arranged the AI and open-source pieces together to form a cohesive book. However, that protection only prevents someone from copying your exact layout and arrangement; it does not give you ownership of the underlying AI or third-party text.