Authentication System FAQ
Acquition, breakage and loss of a IC card
A1. If you put several noncontact IC cards in your wallet together, they can be electromagnetically coupled. As a result, an IC card reader may not read their data. This problem occurs particularly with cards of the same type, such as ICOCA, PiTaPa、nanako、and WAON. Since it is possible your card will not be readable, put it in a separate wallet from your other cards.
A2. There is a commercial soft-magnetic film which you can put between IC
cards.This film might prevent their electromagnetically coupling even in the
same wallet. Please buy this type of film on your own.
For example, the following product can be used for this purpose: http://flux.bz/pass-case.html