[crowbahr]

In addition to the mechanisms people are describing here - passports have a metal mesh in them to disrupt NFC signals. It's not a full faraday cage but it works on similar principles. The passport has to be _open_ to be read from, and then only after you transmit the MRZ will you get anything.

[raron]

> passports have a metal mesh in them to disrupt NFC signals

I don't think that is universally true. At least I can read my closed 2 years old passport with my phone.

[crowbahr]

Hmm the American passports have the mesh afaik - I _thought_ it was part of the ICAO docs (not that that means people do it but still...)

[crowbahr]

Just tested on my American passport - it will not read while closed, either from the front or the back. Opening it up - no issues reading. Seems like there is in fact a faraday mesh or something