Relationships and Resource Linkages in non-compound documents


In a non-compound response document (i.e. no top-level included member), are resource linkages required for a relationships object?

For example, in a non-compound document, would this be a legal representation of a relationship object (note the absence of a resource linkage - the data member is missing):

“relationships”: {
“files”: {
“links”: {
“related”: {
“href”: “”,
“meta”: {}

My reading of the specification is that a resource linkage is only required in order to achieve “full linkage” in a compound document, otherwise they are optional. Is that a correct interpretation?

Clarification: non-compound documents and resource linkages

The spec states

A “relationship object” MUST contain at least one of the following: links […], data […], meta […]

Hence, it is indeed allowed to represent a relationship by just a link.