Would like to make hardware that accepts Apply Pay. What is specification needed?

I'm doing an NFC hardware and would like to integrte (accept) apply pay too. What specification needed to do that? I see squareup did it https://squareup.com/apple-payI want to do it too.

I would recommend starting with the EMV Contacless specification http://www.emvco.com/specifications.aspx?id=21

Would like to make hardware that accepts Apply Pay. What is specification needed?
 
 
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