The REPORT method (defined in Section 3.6 of [RFC3253]) provides an extensible mechanism for obtaining information about one or more resources. Unlike the PROPFIND method, which returns the value of one or more named properties, the REPORT method can involve more complex processing. REPORT is valuable in cases where the server has access to all of the information needed to perform the complex request (such as a query), and where it would require multiple requests for the client to retrieve the information needed to perform the same request.
CalDAV servers MUST support the DAV:expand-property REPORT defined in Section 3.8 of [RFC3253].