The TR3 states in sections 1.10.3, 1.10.4 and 1.12.4 that the reported billing NPI and tax ID must be the information for the billing provider that will be paid and reported to the IRS on the 1099. This implies that the reported NPI and tax ID must be for the same entity to be compliant with IRS reporting requirements. Does non-compliance with these requirements means that a claim can be rejected instead of denied if the tax ID and NPI provided on the claim do not match provider reported registration information within the payer's database?
As you state the TR3 requires the NPI and Tax ID reported in the Billing Provider Name Loop to be for the same entity. Therefore, to be compliant with the 837 TR3’s the NPI and Tax ID of the entity reported in the Billing Provider Loop must belong to the same entity.
Compliance with X12 TR3 syntax has no relevance to the matching of data in a receiver’s database. It is a receiver’s business decision regardless of the compliance of the transaction whether to reject an 837 due to a mismatch of the NPI and Tax ID submitted on the claim against the NPI and Tax ID in their internal database.
On a related issue, RFI 1512 addresses X12’s position on accepting or rejecting non-compliant transactions. That RFI states:
ASC X12 does not govern the receiver's actions when receiving a transaction that is not compliant with the specified implementation guide. Section 2.2.1.1 in TR3s published by the ASC X12 Insurance Subcommittee makes this clear with the statement "The receiver will handle non-compliant transactions based on its business process and any applicable regulations."