Generate 837P for secondary payer. Navjot Singh April 25, 2019 07:14 1 comment Is there any tutorial available on how to write 837P for secondary & tertiary payer. Comments 1 comment Sort by Date Votes Admin April 25, 2019 14:35 We haven't got any other examples that the ones currently available on the website\GitHub. You can always go to X12's examples page, find one that suits your case and download the file. Then use X12Reader to read the file and inspect the structure, either in the debugger or export to XML\JSON. This way you'll be pretty sure how would it look like and it'll be easier to replicate it when generating a transaction with your own data. 0 Please sign in to leave a comment.