There is a single database of non-member records that can hold information about co-borrowers, joint owners, and beneficiaries.  Each record requires a unique SSN/TIN*, and then the records can be linked to any member account for any purpose. 

For example, John Smith might belong to one credit union, and his wife, Mary, belongs to another credit union, both within the same multi-corporation environment.  If both of them wanted their daughter, Julie (not a credit union member), to be listed as a joint owner or beneficiary on certain accounts, a single non-member record could be created for Julie and that same record could be used when setting up joint owner and beneficiary links.  Any required maintenance, such as an address change, would only need to be done to that single record.

*The system has a method whereby "imitiation" SSN can be assigned in situations where an Social Security number is not available.