[GA-6] MUST requirement with only optional subfields

[andorsk]

[GA-6] MUST specify in the EGF any additional requirements for an authorized trust registry. This data will be comprised of the following elements::

[GA-6-1] SHOULD provide Information Trust requirements.
[GA-6-2] SHOULD provide Technical requirements.
[GA-6-3] SHOULD provide Operational requirements.
[GA-6-4] MAY provide Legal contracts.

If MUST supply an EGF with authorized trust registry data, what are the minimum requirements for data? In the case NONE of the sub-conditions are satisfied, what is the expected returned value?