Feeding a textbook to an AI and selling the result: is that OK? Could you show that material to its author?

For healthcare professionals who want to build teaching material, courses or apps with AI and make money from them.

"What if I fed that thick textbook to an AI and turned it into something easier to learn from? That would sell, wouldn't it?"

Turn it into explainer videos. Build comprehension tests. Make a chat that answers questions.

Combining medical knowledge with AI to make something easier to learn from. The idea itself is a good one.

But before you build the buy button, there's something worth stopping for.

Are you allowed to use that textbook that way?

"I bought the book." "I'll credit the source." "The AI rewrote the text anyway." None of those, on their own, settle the copyright question. Feeding material to an AI and publishing or selling the result each need their own check.

This post is not "don't earn money with AI".

It's about not wrecking a good idea with an infringement. And about paying proper respect to the people who wrote the books we learned from.

This is a general explanation based on Japanese law, using legislation and public materials available as of 6 September 2026. It does not guarantee the legality of any particular service. For an actual project, check with the rights holder and a lawyer who knows copyright.

The short answer: selling is fine, but buying the book isn't a licence

There is no blanket ban on selling teaching material made with AI.

Use text you hold the rights to. Get the licence you need. Build your own explanation from facts that aren't protected in the first place. Quote within what the law allows. There are routes to a product.

The distinction worth holding onto is this:

• Learning from a textbook and making your own material
• Taking the textbook's sentences, figures and particular explanations and reworking them into a different product

The names of bones and the anatomical facts are not the property of one textbook. The creative sentences and figures that explain them, and the particular analogies, can be protected. If there is creativity in how the material is selected and arranged, that editing can be protected too.

Obviously, no single author owns the general order in which a topic is explained. What matters is not confusing the medical facts with the expression that book created.

Also, copyright doesn't require registration. It exists from the moment the work is created. A book without a big "no reproduction" notice is not therefore free to use.

"Feeding it to an AI" and "selling it" are separate checks

Rather than treating AI-assisted material as one lump, split it into stages.

With the articles spelled out:

Where these rights are engaged, you check whether you have a licence or fall within a statutory exception. "Only paying members can see it" doesn't make it free either.

Even when the finished product is your own writing, the input and storage stage can still be a problem. And even when the input is lawful, that doesn't mean the output is yours to sell as-is.

Here are the lines you hear most often, and where they actually land.

Now, one at a time.

"But I heard AI training is free in Japan"

The provision people mean is Article 30-4 of the Copyright Act.

It permits certain uses without authorisation where the purpose is not the "enjoyment" of the thoughts or feelings expressed in the work, such as information analysis. But it is limited to what is necessary, and it does not apply where it would unreasonably prejudice the interests of the rights holder.

Awkward wording, but the thing to remember is that "it's for AI" does not by itself permit everything.

Take retrieval-augmented generation, where a system searches your material to answer questions: RAG. The Agency for Cultural Affairs' Views on AI and Copyright distinguishes copying material for that purpose where there is no aim of outputting the original creative expression, from cases where there is such an aim. For the latter, Article 30-4 is treated as not applying.

Equally, it is not a provision that switches off the moment money is involved. Commercial or not is one factor; what you are using it for, and how, matters more.

Where Article 30-4 doesn't apply, quotation, or Article 47-5 on minor uses incidental to search and information analysis, may be worth considering. That does not mean "keep the answers short and it's fine".

And when an AI service says "commercial use permitted", that is about the service, not about the textbook you are feeding it. You need to check the rights in the material and the terms of the service, both.

"Just cite the source" is the misunderstanding to watch most closely

Citing your source matters.

But a citation is not a permission slip.

To use text or figures as a "quotation" under Article 32, the work must already be published, and the use must meet the conditions of fair practice and being within a justifiable scope for the purpose of the quotation. The Agency for Cultural Affairs lists factors such as the necessity of the quotation, clearly marking the quoted portion, and the main/subordinate relationship between your own commentary and the quoted part. Article 48 covers indicating the source.

In practice, at minimum, check:

If the conditions are met, quotation works in paid content too. Conversely, publishing something for free does not license a use that fails the conditions.

Showing a figure from a textbook to the extent needed to critique or examine it is not the same thing as "it's a handy figure, so it becomes the centre of my material".

And a bibliography at the end may not be enough: if a reader can't tell which quotation corresponds to which source, the source indication may be insufficient.

Something like this works:

Quoted from: Author, Title, nth edition, Publisher, year, p. N, figure N.

Keep "references", where you checked a fact and explained it in your own words, separate from "quotations", where you use someone else's expression.

Listing references is not always a legal obligation under copyright law. Even so, for medical teaching material, I think you should make the basis of an explanation traceable. And where a licence requires attribution, you follow those terms too.

"It's educational" and "the AI reworded it" are not free passes either

Material for healthcare professionals is educational, obviously.

But an educational purpose and the statutory exception for use in classes at an educational institution are not the same thing.

Article 35 covers educational institutions other than those established for profit, for use to the extent necessary in the course of a class. An online course or material an individual sells is not covered simply because it is "educational".

Likewise, Article 30 on reproduction for private use covers use within your own or your family's limited circle. Producing material to sell doesn't fit inside private use.

And if you have an AI reword something, where the original creative expression remains, reproduction and adaptation questions remain with it. Summarising or turning it into video isn't lawful merely because the format changed.

Working through a book chapter by chapter, rewording each and selling it. Tracing a figure and changing the colours. Publishing a paid chat that will produce the text passage by passage. These designs deserve particularly careful checking of how much of the original expression they use.

The question isn't "how many books did I mix?" or "what percentage did I rewrite?" It's what you are using.

A pre-sale checklist

Here is a practical flow based on the legislation and the Agency's materials. It is not an automatic verdict where reaching the end means you're legal. It's for deciding where to stop, and what to check, when something is unclear.

If you get through that, consider selling, and keep a record of the licence terms, the sources, the date you checked and the revision history.

"Material I wrote myself" needs care too. Even your own text may not be freely reusable if you assigned the rights to a publisher or a society, or if it contains someone else's figures.

For a chat-style service, check not just one answer but how much of the original text comes out when you keep asking.

When you ask about a licence, "can I use this for reference?" doesn't communicate anything. Show the book and the specific parts, how it will be fed to and stored by the AI, what processing happens, sample outputs, the sales format and the term of use.

The rights in the text and in the figures or photographs may sit with different people. Through the publisher's contact point, confirm who you need permission from, and for what.

For medical services, copyright isn't the end of the checklist

What follows depends on what your service does. Not every piece of material attracts every regulation.

For patient information, design the material stage around fictional cases or properly cleared sources. Writing "made with AI" or "created by a healthcare professional" does not remove any of these obligations.

Separately from the legal checks, the medical content itself needs review: which edition you used, when the information was updated, whether the explanation matches the evidence, and a human step to catch AI errors and dropped conditions.

"I didn't know" may not keep you selling

Where there is an infringement, the rights holder can seek an injunction to stop it. Article 112 of the Copyright Act covers injunctions; Article 709 of the Civil Code covers damages.

An injunction can be sought regardless of the infringer's intent or negligence. Damages have their own requirements including intent or negligence, and criminal penalties under Article 119 and related provisions turn on intent and other elements. "Use it unknowingly and you're instantly a criminal" is too crude, but so is "I didn't know, so nothing happens".

What worries me isn't the size of the penalty.

What if you start selling, build up customers, and then have to stop? You may owe your buyers an explanation and have to rebuild the material. The trust in a service carrying your name may wobble.

Which is why the checking belongs before you start building, not after it sells.

Rather than going around the author, you can build it with them

"I want to use the textbook, but the rights are hard to check."

The options aren't only "go ahead without asking" or "give up".

Medical publishers often have a contact point for reproduction and quotation requests. The industry body, the Japan Medical Publishers Association, publishes its thinking on reproduction and quotation along with where to ask. Some publishers have their own position on AI use and paid licences, so asking the publisher of the book you want is the fastest route.

A publisher's position isn't the last legal word, of course, and it doesn't mean every proposal gets approved.

Even so, there is a path where the people who accumulated the knowledge and the people building new learning experiences work together.

I would rather ask "I want to deliver the value of this book as this kind of learning experience. Under what terms could we do that together?" than announce "I'm turning this book into a different product with AI."

Checking rights isn't work that stops you creating. It's work that makes what you create sustainable.

Manners towards the author. Respect for the people who built the knowledge

A clear explanation, careful figures, a structure you can follow without getting lost.

When we hand things to an AI, we tend to call all of it "sources". But in there is the work of the person who wrote it, the person who drew it, the person who checked it.

What the law protects is creative expression, not the effort or the hours themselves. Even so, I want us to remember the work behind that expression.

There's no need to hold back from learning, or from lawful quotation. Respecting rights and stopping the sharing of knowledge are not the same thing.

But being able to shape something quickly with AI doesn't mean you built the foundation too.

What did you learn, and from whom, and where did you add your own work? I want to make products where I can answer that.

"Could you show that material to its author?" is not a legal test.

But it is a decent question for working out what kind of maker you want to be.

Let AI make the work faster. Respect the authors, get the permissions you need, pay what you agreed. Then add new value with your own expertise and ideas.

If you're thinking about monetising, care about how you make it as much as how you sell it.

Books and teaching material built up over years and decades are not simply "data to feed an AI". Behind them are authors, editors, the people who drew the figures, and researchers who accumulated the work.

Follow the law, obviously. But before that: manners towards the author, respect for the work.

Then use AI on top of that to add something new. That's the kind of AI use I'd like to see more of.

One last check before you ship

Everything above, in a form you can tick off. Your checks stay on this device, so use it while you build.

Sources

Legislation, public explanations and rights-holder guidance are listed separately. Explanations from publishers and industry bodies are their own positions and procedural guidance, not court rulings. All checked on 6 September 2026. All sources are in Japanese.

1. Agency for Cultural Affairs, "AI and copyright" (the hub page for the views, checklists and related material)
2. Agency for Cultural Affairs, "Views on AI and Copyright" (15 March 2024; input to generative AI, Article 30-4, AI output and infringement, RAG)
3. e-Gov, "Copyright Act" (the main articles referenced here: 19, 20, 21, 23, 27, 28, 30, 30-4, 32, 35, 47-5, 48, 112, 119)
4. Agency for Cultural Affairs, "Copyright text" (conditions for quotation, indicating sources)
5. Japan Medical Publishers Association, "On reproduction and quotation of works" (reproduction and quotation of medical books and journals, where to request permission)
6. Personal Information Protection Commission, "Alert on the use of generative AI services" (PDF)

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This post is not legal advice about any specific project. For an actual product, gather the books you plan to use, how they will be fed in and stored, and samples of the output, and check with the rights holder and a lawyer who knows copyright. The Agency's "Views" do not substitute for a court's judgment in an individual case.