By a copyright agreement, copyright may be assigned or fully transferred, and such an agreement must be concluded in written form.
A copyright agreement includes: the names of the contracting parties, the title or identification of the copyrighted work, the rights that are the subject of the assignment or transfer, the amount, method, and deadlines for payment of copyright remuneration if agreed upon, as well as any substantive, territorial, and time limitations, if they exist.
If the use of the copyrighted work results in a profit that is clearly disproportionate to the agreed-upon copyright remuneration, the author or their heir has the right to request an amendment of the copyright agreement in order to eliminate the disproportion. If no remuneration was agreed upon, and the revenue generated from the use of the copyrighted work exceeds the costs of its use to a degree that enables payment of a remuneration, the author or their heir has the right to request an amendment of the agreement to include remuneration. These rights are subject to a statute of limitations of two years from the date the disproportion or revenue was discovered, and no later than six years from the end of the year in which the disproportion occurred or the revenue was generated.
The author or their heir may withhold permission previously granted or revoke a transferred economic right if the licensee or right-holder does not exercise the acquired right, or exercises it to a lesser extent than agreed upon, thereby endangering the interests of the author or their heir—unless this is due to reasons for which the author or their heir is responsible. Before withholding permission or revoking the right, the author or their heir must notify the licensee or right-holder and provide a reasonable period for them to begin exercising the acquired right or to exercise it in the agreed-upon scope. This right arises after two years from the conclusion of the copyright agreement, or from the delivery of the work to the right-holder if the delivery occurred after the agreement was concluded.
The author may withhold permission granted, or revoke a transferred economic right if they believe that exploitation of their work could damage their creative or personal reputation, and this is due to circumstances that arose after the agreement was concluded and for which the right-holder is not responsible. In such a case, the author is obligated to compensate the right-holder for any actual damage incurred.