Your doubt tells us that your PIN is not a palindrome. The second most common PIN is 1-1-1-1, followed by 0-0-0-0 (says http://www.datagenetics.com/blog/september32012/ ), and looking at the top 20 numbers, over 10% of the people have a palindromic PIN. (If selected randomly, that should be 2%.)

So either the police get called a lot, or there's some special flag that say "palindrome PIN - false alarm" (and it must be supported for international cards) ... or it's simply not true.

The same place also had a security system for a critical data center room: Opening the door from the outside (i.e. entering) would increment a counter by one, opening it from the inside would decrement it. If the room, according to that counter, was supposed to be empty, any movement within would trigger the same silent alarm. The system worked safely up to the point where two people entered together, one of them left the room and the other one's badge had a temporary malfunction. We were quite impressed with how quickly a large assortment of police would show up, guns blazing and all ;-)

1: https://www.google.com/patents/US5731575

So patent examiners cannot just look at something and say, "this is crap, no patent for you". They have to prove a patent application invalid. There are many ways to do this, but the most common is by showing sufficient prior art. If they cannot find one or more previously published works that disclose each and every element of the claim, they must allow it. Apparently the examiner could not find evidence of somebody thinking of this before, and so it was allowed, regardless of how novel it appears to us now.

Another way to find an application invalid is to show that it does not disclose enough detail about how to implement the invention. That is probably why this patent (and most others) are really long-winded.

I think of touch UIs and the patents there, for example Apple's rubber-band scrolling patent[2]. Sure, it's quite probable that no one thought of this before if they weren't designing touch UIs. And even if they were, they might have thought of that, plus several other ideas, while developing. Why should this make any difference?

For instance, no one has made scrolling that intentionally segfaults if you scroll fast enough (or insert other silly thing here). You won't find prior art on this. Should it be eligible for a patent just because it's novel? There should be some sort of criteria where the effort required to invent something is taken into account. If it's likely to come about merely as a result of playing in the space, then what does the public gain by issuing a patent?

What knowledge is contained in the "reverse PIN dials cops" that merits protection? Even if nobody had that idea before (or bothered to document it), what does that matter? If you patent can be constructed just by asking a simple question ("think of some ways to alarm when being robbed at an ATM"), well that should be grounds for it not being valid.

Edit: Another example. Things like algorithms. Look at a simple database indexing system: ISAM. Sort your data, sample every so often to form an index. Repeat if the index is too large. Ta-da. Going back far enough, this was very novel. But any worker that had to figure this problem out would arrive at the same solution. It's nearly as fundamental as binary search.

1: https://en.wikipedia.org/wiki/Inventive_step_and_non-obvious...

2: http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=H...

One line of reasoning is that there are not enough people "merely playing in some space" to find more solutions to problems. This is not just theoretical. There is empirical evidence based on historical data that showed how the introduction of patent protection to previously ineligible arts influenced innovation. It finds there was more innovation in areas where previously protection was not available or where it was too easy for competitors to rip off your inventions. See http://www.jstor.org/stable/4132712 for instance.

> If you patent can be constructed just by asking a simple question...

Many scientists, mathematicians and engineers will tell you that the best way to solve a difficult problem is by framing it correctly. Put another way, you have to first ask the right questions. The solution may become obvious then, but it may be very hard to first ask the right question. And hindsight is a very powerful bias. What may seem like a simple question today may not actually have been so before it was posed.

This is also one of the many problems with requiring effort as a criteria. Besides being difficult to quantify in general, how do you measure the effort required to formulate the right question? How do you quantify flashes of insight? Maybe a person has 20 years of experience in some field X, but sees a problem and reaches a solution in 20 seconds. Was the effort required 20 seconds or 20 years?

Wells Fargo and a couple others allow anywhere from 8-16 as their maximum, though I reduced mine to 12 because some ATM's were kind of finicky at the longer lengths.

Luckily (hah) working for a US company so I don't get enough time off to actually go overseas, so it's never been something I had to worry about.

Edit: It doesn't seem so weird anymore either. I used to get questions all the time from Cashiers, like "Wow, I didn't know your PIN could be longer than 4". But I haven't been asked about it in 1-2 years.