How to Permanently Preserve E-Books

E-books Are Data, So in Theory They Can Be “Semi-Permanently Preserved”

There are two key points to consider when aiming to permanently preserve e-books:

1. Whether you actually own the e-book data
2. How to preserve the data itself permanently

Do You Own the E-Book Data?

When purchasing an e-book, there are two cases: buying “the right to view it on a platform” or purchasing the data itself.

In the former case, you are merely purchasing a “license,” so you cannot move or store the data independently, since it exists only within the app.

In the latter case, you can manage the data yourself. Public domain e-books, such as those from Aozora Bunko, fall into this category. Since you have ownership of the data itself, you can preserve it semi-permanently as long as the storage medium doesn’t fail.

Can the Data Itself Be Preserved Permanently?

Even HDDs or USB drives have limited lifespans, so permanent storage is impossible. In addition, connection standards such as USB evolve over time, raising the question of whether current data can still be read decades from now.

For example, iPhones from 10 years ago used proprietary connectors, but today they have been replaced with Lightning, and devices that support the old connectors are now rare. Similarly, even if the data itself remains intact, the hardware required to read it may no longer exist.

Currently, saving data to the cloud is the most common solution, but since no cloud service is guaranteed to exist forever, it cannot be considered a permanent preservation method.

The same applies to e-books purchased through an e-book platform: as long as the platform operates, you can download your purchases anytime, but there is always a high risk that the platform could shut down or exit the business suddenly.

Can E-Books Be Permanently Preserved Through Screenshots?

Some sites suggest that taking screenshots of e-books purchased through a platform allows you to preserve them as your own data.

Technically this is possible, but some platforms prohibit screenshot saving in their terms of service, and certain apps may even prevent screenshots from being taken.

Moreover, taking hundreds of screenshots for a novel or nearly 200 pages for a comic is extremely labor-intensive. In this case, it is much easier to simply buy the physical book, wrap it in protective covering, and store it—which is a far more reliable method of preservation.