All Unified Procedure Step Instance Attributes in Table CC.2.5-3 in PS3.4 with a Return Key value of 1 and 2.

All Unified Procedure Step Instance Attributes in Table CC.2.5-3 in PS3.4 with a Return Key value of 1C for which the conditional requirements are met.

All other Unified Procedure Step Instance Attributes passed as {attributeID} query keys that are supported by the Origin-Server as matching or return attributes

All other Unified Procedure Step Instance Attributes passed as "includefield" query values that are supported by the Origin-Server as return attributes.