The following information is taken directly from the eRA website:

“Is a DUNS number required for every subaward/consortium organization?"

Ideally yes. The 'Organization DUNS' is a required field on the 'Research & Related Budget' form, regardless of the budget "type"-project or subaward/consortium. However, at the subaward level, neither Grants.gov nor NIH currently validates on the accuracy of that field. For subaward organizations, eRA Commons only validates that the DUNS field contains a value and that the value is not the same DUNS number provided by the prime applicant. At this time the eRA Commons does not do any further validations on the accuracy of the number. So for now, if a subaward/consortium organization is unable to secure a DUNS number in time, then a value of nine zeros can be entered in the DUNS field on the subaward/consortium budget component. This requirement may change over time.”