Pursuant to Art. 3 para. 4 CopA, the protection of the works used in the derivative work remains reserved. If the original work enjoys copyright protection, it does not lose this when a derivative work is created from it. This means that the consent of the author of the original work must be obtained to produce a derivative work.
Example: an assistant would like to revise old lecture notes of the lecturer and update them; they must obtain the lecturer’s consent to do so.
This means that work users who want to use the derivative work need the consent of both the author of the original work and the author of the derivative work.
Example (related to the previous example): students want to scan the updated lecture notes and publish them on the Internet. Then they need to ask for the lecturer’s and for the assistant’s consent.
If they do not have the consent of the afore-mentioned people, the (original) author’s right to decide whether, when and how the work may be altered, as specified in Art. 11 para. 1 (a) CopA, and the rights to use the work specified in Art. 10 CopA can be infringed, unless there is a case of private use.