Unsetting Single-value and Multi-value Properties

5.4.4.3.11 Single-value Properties
[...] To unset the property, the client must submit form data in which the propertyId MUST be present and the propertyValue control MUST NOT be present.

5.4.4.3.12 Multi-value Properties
[...] To unset the property, NO propertyValue control MUST be present.