According to section 1.4.2 of the 005010x279 guide and by the Patient/Subscriber WEDI SNIP Audio Cast on this subject from 8/22/2009, a patient is considered a subscriber if he/she is uniquely identified by the payer.
Subscribers are sent in the 2000C loop of the 270 & 271. Otherwise, if the patient is a dependent who is not uniquely identified, then the patient is considered a dependent, thus sent in 2000D. What happens if a payer
uniquely identifies their members (thus all would be considered virtual subscribers) but wants to include the actual subscriber in 2000C along with the actual dependent in 2000D in both the 270 & 271? They need this because claims ultimately
reject if the actual subscriber is not known. Is there any compliant workaround to send the subscriber in the data if the dependent patient is a "virtual" subscriber who is uniquely identified?
You are correct that in the 005010X279A1 a dependent patient is considered to be the subscriber if that person can be uniquely identified by the payer with their own payer assigned Member ID. The 005010X279A1 TR3 does not support sending both the Subscriber and the Dependent patient information when both have been assigned unique Member ID’s. When the payer can identify the Dependent patient by their unique Member ID, the Dependent is considered to be the Subscriber in the Eligibility inquiry.
The same logic exists in the 837 Claims. The Dependent is deemed to be the Subscriber if they can be uniquely identified by the payer. If the payer can identify the Dependent patient with a unique payer assigned Member ID, there should not be a need to provide the actual Subscriber information in either the Eligibility or Claims transactions.