It is not mandatory to use the symbols ©, ™, or ® in the Benelux.
The © symbol is used for works protected by copyright. It is often included in texts to indicate that the work is protected under copyright law and originates from the creator.
The ™ symbol is used to indicate that there may be rights associated with a name or sign, regardless of whether the trademark is registered.
The ® symbol is used to indicate that a trademark is registered. This symbol is typically placed in the upper right corner of the trademark.