[BjoernKW]

Something like this has been done before, albeit in the form of objects like rings:

http://www.ds72.com/projects/oyster-ring

So while possible unfortunately tampering with Oyster cards is frowned upon by TfL. It might not technically be illegal but it'll certainly run you into problems when checked by traffic inspectors.

The answer to this StackExchange question gives an in-depth explanation of the Oyster card's cryptographic architecture, which shows that the card being as tamper-proof as possible is very much by design:

https://electronics.stackexchange.com/questions/78013/can-i-...

[mseebach]

I would suspect that your troubles go beyond "frowns". A ticket inspector wants to see a valid oyster card, not a party trick, and whether it scans or not, I don't think it's a high bar to argue that a tampered with card isn't valid, period.

(Officially, at least. I've seen them happily scan the outsides of people's wallets.)

[DanBC]

Not sure why you got downvoted. English rail laws are pretty clear about tickets.

http://content.tfl.gov.uk/tfl-conditions-of-carriage.pdf

> 5.1 All photocards and Oyster photocards remain our property and must not be intentionally damaged, altered or tampered with in any way. We may withdraw or cancel your photocard or Oyster photocard at any time

The railway bylaws say this:

https://www.gov.uk/government/uploads/system/uploads/attachm...

> 20. Altering tickets and use of altered tickets

> (1) No person shall alter any ticket in any way with the intent that an Operator shall be defrauded or prejudiced.

> (2) No person shall knowingly use any ticket which has been altered in any way in breach of Byelaw 20(1).

Which makes it sound like this tampering would be okay, but they also say this:

> (1) In any area not designated as a compulsory ticket area, no person shall enter any train for the purpose of travelling on the railway unless he has with him a valid ticket entitling him to travel.

> (2) A person shall hand over his ticket for inspection and verification of validity when asked to do so by an authorised person.

...and it's likely TfL won't see these as valid tickets.

[Tharkun]

Why isn't anyone protesting those TOS? Them having the apparently unqualified right to cancel the card you paid for is unacceptable.

[falcolas]

> having the apparently unqualified right to cancel the card

Is unfortunately required to handle the various con artists and scammers who would exploit loopholes the TOS.

Yes, I believe you can be in the wrong while following the letter of the law; that's part of the reason why we have so many damned laws: to close loopholes exploited by assholes.

Of course some asshole in the system can abuse that clause right back, but that's the cost of doing business with people on both sides.

[kryptiskt]

You're buying the service, not the card.

[mseebach]

And it being a public service, they generally can't deny you the use of it (at least not 'unqualified', I'm sure there could be some sort of police or court order taken out against people) - but they can specify exactly how you're going to pay for the service.

Also, I'm pretty sure "cancelling" means "forced reissue", not forfeiture of a legitimate ticket or balance.

[DanBC]

You'd get to challenge the ToS in court if TfL were unfairly applying it.

[isostatic]

The oyster remains property of TFL, the inspector can withdraw the oyster from use. If your skin is in the way, oh well.

[marklyon]

I remember that movie. It's all fun and games until TFL sends an Oyster collector after another Oyster collector.

[tjmaglio]

RingTheory makes rings that can access the MBTA (mass transit) in Boston. The product is the "Sesame Ring" and they have partnered with the MBTA on this. http://www.ringtheory.com/#home