There are 11 possible payers that can be defined for a claim in the 837: the destination payer identified in Loop 2010BB, and up to 10 other payers identified in 2330B Loop(s). SBR01 indicates the sequence of each of the possible other 10 payers (assuming all payers are known).
However, the repetition factor for Loop 2430 Line Adjudication Information is set at 15.
Why 15? What are the extra iterations beyond 10 of Loop 2430 for? Or is that an oversight and it should be 10 too so that it agrees with the maximum number of other payers allowable?
This issue is explicitly addressed in guide 005010X223. Section 1.4.1.4 Coordination of Benefits - Service Line Procedure Code Bundling and Unbundling, identifies that services could be unbundled by a payer. If that happens, then 1 submitted service could have been returned by a prior payer as unbundled into two or more services. Each of those other unbundled services would need its own 2430 loop, hence requiring that more 2430 loops be possible that the number of other payers possible in the 2320 loop.