Represents the "Subtype" entry of the point data dictionary object.

It is a required entry defined as part of the PDF 1.7 Extension Level 3 specification.

It contains a string representing a PDF name object.

This item must always be provided and must always take the value "Cloud".

For definitive details see:.

Adobe Supplement to the ISO 32000, BaseVersion: 1.7, ExtensionLevel: 3; Table: 8.111d, page 53.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 272, page 602.