“Apple’s 575 million active accounts, which is tracking ahead of our 600 million year-end 2013 estimate, is the largest credit-card linked account base, making it an obvious payments platform over time. Apple often saves new feature/service introductions for its hardware refresh – most notably Siri with iPhone 4S (Oct. 4, 2011).” [edited slightly to unpack abbreviations]

And sure enough, on Tuesday morning the U.S. Patent Office granted Apple (AAPL) 37 patents that included, as Patently Apple reports, an “E-Wallet” patent for parental controls and a “simplified wireless data transfer” patent that would allow an iPhone to make mobile payments without relying on NFC (near field communication) technologies.

Of course, just because Apple patents a technology doesn’t mean it will develop it. But at this point the company has amassed quite an arsenal of patents covering mobile payments. Patently Apple has collected them in its Archives.