The late artist Prince is associated with creativity and excellence for his music and performances. Now his name is associated with excess taxes and the chaotic management of his estate. Prince died in 2016 without a will or even a list of his assets. And now the IRS is challenging the $82 million valuation of his estate, which includes the rights to his music and his recordings, claiming a value of $163 million, and asking for an additional $38.7 million in taxes, thank you very much. The estate is cash-strapped, and who knows how those handling it are going to pay the additional taxes, plus penalties and interest?

Although Prince is an extreme example of what happens when you don’t do any estate planning, it’s not uncommon that a decedent’s ownership of copyrights, patents and other intellectual property is ignored. Many people think this is only the concern of celebrities, but in this day and age, when a YouTube video can go viral or an internet domain name can mean the difference between fame and obscurity, everyone has some intellectual property rights. That means everyone should consider how those rights are managed during their lifetime and after their death.

Intellectual property rights are divided into two types by the World Intellectual Property Organization—industrial property rights and copyrights. Industrial property rights include patents, trademarks and service marks, designs, and locations. Copyrights cover artistic works and reproductions, broadcasts and recordings of those works.

The two types blur together, since a person can have both a copyright and a patent on the same idea. Both are the intellectual creation of one or more individuals, in contrast to the physical or electronic object that intellectual creation embodies. Copyrights, patents, trademarks and other intellectual property laws protect the creators’ value in their ideas by restricting and controlling who benefits from the control and reproduction of the physical or electronic object.

Copyrights apply automatically to original works of authorship that are fixed in some medium where they can be reproduced or communicated either directly or via some device. Although automatic, copyrights can only be enforced after registration with the U.S. Copyright Office. The use of © as a copyright symbol or the words “all rights reserved” are no longer necessary to enforce a copyright.

Once registered, copyrights are good for the lifetime of the author, plus 70 years (or the lifetime of the last surviving co-creators, plus 70 years). Copyrights on works made for hire or published anonymously last for a term of 95 years from publication, or 120 years from creation.

Copyrights, as the right to control and reproduce something, are separate from the physical art objects themselves. An artist or an author can sell a piece of art or a writer can gift a manuscript to somebody else, yet still retain the copyrights. Creators have often sold copyrights to other people at a small fraction of the true value of the intellectual property asset.

Since 1976, creators have had the right to terminate the transfer of their copyright, but this termination of the transfer of their copyright must occur within 40 years of the transfer, or 35 years after the first publication. Because this right of termination is not transferrable except by a specific reference to the right in the creator’s will, if a creator dies before the termination time has expired, the right of termination goes to the creator’s intestate heirs, and not according to their will or trust.

Industry intellectual property is regulated under different rules. Unlike copyrights, it is not generated automatically. And you lose the right to the intellectual property if you make and sell an object before filing for a patent or if you wait so long that someone else files before you. Also, industry intellectual property needs to be maintained, documents needs to be filed and fees paid to establish and maintain those rights.

Estate planning for intellectual property requires that those rights are properly transferred, either during the owner’s life or (like the right of termination) at death. This involves cataloging and valuing the property, and determining who has existing rights in it. This can vary depending on whether it is classified as a copyright or industry right. Intellectual property rights cannot be transferred by a transfer of the physical object, such as a work of art. The result is that one person may own the right to the artwork but the remainder beneficiaries of the estate own the copyrights to reproduce it.

The valuation of intellectual property assets also poses a challenge. Unlike investment assets or real estate, intellectual property begins as valueless since it represents only an idea or ideas. It’s what happens as a result of that idea that creates value. So intellectual property value ends up being based on the best guess as to what the cash flow will be from the licensing, assignment or use of the copyright or patent over time.

I know of one case where copyrights to music were donated to a charity and valued at a certain amount. Later, the music was used in a movie, which suddenly made it very popular, and the annual royalties rose to 10 times their previous amount. This required the value of the charitable deduction to be recalculated each year for income tax returns.

In this electronic age, there are also new issues such as the computer-generated representations of people long dead. People can’t control their image in death, but their heirs have the rights to control it, so long as those rights are properly transferred.

Domain names, meanwhile, are valued separately from the content on a website—and can be sold.

With social media, there is more focus on the moral rights of creators to control their work not only by copyright and patent laws, but also under the protection of privacy, defamation and publicity laws. For living artists, the Visual Artists Rights Act of 1990 protects the artist’s rights both to have artwork properly attributed to them and also to remain anonymous.

Finally, artists need to consider the income tax on the financial gain from their creativity. Royalties, which are payments for the right to use intellectual property assets, are considered ordinary income for the creators, not capital assets. But those who hold the copyright or patent of something created by someone else may be able to treat the sale or transfer of the property as a long-term capital asset.

With so many things to consider, you can see why Prince never did any planning for his estate. Had he even taken the first step in planning—i.e., cataloging and inventorying his intellectual property—it would have been a huge step forward. Now, without any record of what he owned or how much it is worth, his heirs may be facing nearly $40 million in additional estate taxes.

Do not assume this is an issue limited to famous celebrities. If you have a website or post on social media, you have intellectual property. Unless your estate planner knows about and plans for the transfer of those assets, you too may be handing them a mess.

Matthew Erskine is managing partner of Erskine & Erskine in Worcester, Mass., which provides legal and fiduciary services for unique assets.