148 votes
Accepted

Scam caller asked for last 4 digits of card. Fake number doesn't fool him, does he have my full number?

He was probably trying to impersonate you on a site that legitimately knows your card number, perhaps your card issuer itself. Such a site would challenge your identity by asking for your last four ...
erickson's user avatar
  • 838
134 votes

Why do credit cards have their number and CVC code printed on them for all to see?

Ultimately you don't bear the fraud risk so you you don't set the risk tolerance. The three digit code, the whole card number, chip and pin, chip and signature, the signature on a receipt, the info ...
quid's user avatar
  • 49k
130 votes
Accepted

Can the stock price go up even if no one is buying?

Let’s take a step back. Prices have their origin in the fact that there are buyers and sellers. If as you ask “NO ONE” is buying, there is no price that can be reported. No transactions will occur. ...
JTP - Apologise to Monica's user avatar
69 votes
Accepted

Isn't the security of credit cards with chip worse than with signature?

One advantage of the chip cards is that the card information needed to make purchases can't be easily skimmed or "stolen". Another is that it is more difficult to create a fake physical card. These ...
BrenBarn's user avatar
  • 24k
58 votes
Accepted

Why do credit cards have their number and CVC code printed on them for all to see?

The purpose of the security code is not a secret PIN. The purpose is to "prove" that you have the physical card in your possession at the time of purchase. It is only used when the merchant cannot ...
Ben Miller's user avatar
  • 115k
54 votes

Do institutions have right to ask for your credit card security code and all other CC data?

It means that the merchant (here, a university)'s process is to deceive their processor by falsely submitting the charge as a "CVV2 with Magnetic Stripe failure" transaction. Having the card present ...
Ben Voigt's user avatar
  • 6,788
53 votes

Can the stock price go up even if no one is buying?

What you are describing is similar to what used to happen every night on a stock exchange that isn't open 24 hours (before after-hours trading existed), since after the exchange closes no one was ...
TTT's user avatar
  • 47.2k
45 votes

How can I get the same protection shopping with a credit card, without using a credit card?

Dave Ramsey is well-meaning, but wrong sometimes. Aren't we all. What Dave is really saying is "You can't have credit cards because I don't trust you to use them responsibly". I realize that ...
Harper - Reinstate Monica's user avatar
37 votes

Do institutions have right to ask for your credit card security code and all other CC data?

This violates PCI-DSS They are only allowed to use security code or fullstripe data momentarily during a transaction. They are not allowed to retain it, even for a minute. Even worse, this form ...
Harper - Reinstate Monica's user avatar
35 votes
Accepted

Is CFD trading a good idea?

No, it's not a good idea. You started by saying you'd like to invest, but then mentioned something that's not an investment, it's a speculation. Both Forex and CFDs are not really investments. They ...
JTP - Apologise to Monica's user avatar
34 votes
Accepted

How can I prevent future card fraud?

For starters - by not using debit cards. It has been noted on this site numerously that credit cards are safer. Not only in the US, Visa/MasterCard dispute resolution rules for credit cards are ...
littleadv's user avatar
  • 166k
32 votes

Scam caller asked for last 4 digits of card. Fake number doesn't fool him, does he have my full number?

The last digit is a check digit that uses the Luhn algorithm to help avoid data entry errors, but you need all of the previous digits to calculate the check value. It is possible that they have a &...
mhoran_psprep's user avatar
28 votes

Isn't the security of credit cards with chip worse than with signature?

I don't have much to add other than your signature is not required to process a charge. Signatures are kept on file for validity in the event you dispute a charge. Your signature isn't held in some ...
quid's user avatar
  • 49k
27 votes

Do institutions have right to ask for your credit card security code and all other CC data?

The reason that they are asking for it is because they need it in order to process the credit card payment. They are required by their credit card processor to enter it. If you do not provide it, they ...
Ben Miller's user avatar
  • 115k
24 votes

Company asking for card details to refund over email

If it is a well known company that wants to give you a refund, I would not worry about giving them your credit card number. However, I would never type my credit card number into an e-mail message. ...
Ben Miller's user avatar
  • 115k
21 votes

Is CFD trading a good idea?

Now the question: is advisable for a beginner to speculate in CfDs? No. If not, is there a better way to invest with a small amount of money? In the US, and I'm sure this carries to the UK, most ...
quid's user avatar
  • 49k
21 votes
Accepted

How is double-spending prevented in traditional banking?

There are a lot of details involved in the answers to your question. Some of them would require specialized knowledge and is institution dependent...you would need someone who writes or oversees code ...
farnsy's user avatar
  • 15.1k
20 votes

Is my investment safe if the broker/bank I'm using goes into insolvency?

A simple insolvency or bankruptcy of a broker shouldn't affect that status of ETFs and stocks you own, because they are not part of the assets of the broker. This is different from fractional-reserve ...
jpa's user avatar
  • 1,086
19 votes

Can the stock price go up even if no one is buying?

The price of the stock can be reported at its bid or ask price or last trade price. No one needs to buy or sell the stock for the bid/ask price to change just like no one needs to buy merchandise from ...
Glen Pierce's user avatar
  • 2,573
19 votes
Accepted

Credit card numbers on the back - is it not less secure?

The numbers-on-the-front design was necessitated by offline credit card processing, in which the card was put on to a device that imprinted the card on to a piece of carbon paper for later processing. ...
phyrfox's user avatar
  • 764
18 votes

Why are cheques so insecure?

Why has no such method been implemented? Checks aren't always deposited/cashed in a timely fashion. Also, a single account can have multiple checkbooks, and therefore there's no requirement that they ...
Hart CO's user avatar
  • 69.1k
18 votes
Accepted

Why are cheques so insecure?

Why are cheques so insecure? Short answer: because banks bear the risk of check fraud, and any wholesale change in the check payment system is very complicated and expensive. Instead they work to ...
David Browne - Microsoft's user avatar
17 votes

Why do credit cards have their number and CVC code printed on them for all to see?

The main purpose of the security code is to prevent hacked card information from being reused. The main way that this is accomplished is by requiring that payment processors do not store this code ...
BobtheMagicMoose's user avatar
17 votes

Is it possible to brute-force or accidentally use someone else's credit card?

Not even close. Let's start with the check digit, the last digit in your credit card number. It is calculated on a public formula, and many web pages have simple Javascripts to check (locally, no ...
Harper - Reinstate Monica's user avatar
16 votes

Scam caller asked for last 4 digits of card. Fake number doesn't fool him, does he have my full number?

More likely he had nothing and was trying to get you to read out the entire number "so we can correct it." Or, as @freiheit suggested, more likely they were trying to use this to ...
keshlam's user avatar
  • 43k
14 votes
Accepted

Is it a good idea to scrape away my credit card's cvv code?

If you would like to scrape the security code off the back of the card, there is nothing stopping you. However, it may hurt the usability of the card, and you won't be gaining as much security as you ...
Ben Miller's user avatar
  • 115k
14 votes

Why do credit cards have their number and CVC code printed on them for all to see?

You are asking why the card number and the security code are printed on the card. In both cases, let's review a bit of history: The card number The card number (called PAN in the industry) is just an ...
jcaron's user avatar
  • 3,942
14 votes
Accepted

Is my investment safe if the broker/bank I'm using goes into insolvency?

I'm German, but not a lawyer, so I can't really make sense of the statute of the Entschädigungseinrichtung alluded to in another answer. But the reputed German finance/consumer magazine "...
henning's user avatar
  • 1,657
14 votes

How can I get the same protection shopping with a credit card, without using a credit card?

In the United Sates the safest method of paying is with a credit card. There is always a lag of weeks between the usage and the pulling money from the bank account. There are ways to dispute ...
mhoran_psprep's user avatar
13 votes

Can I dispute charges where I did not enter CVV?

The dispute will not center around whether you gave the CVV number or not. The dispute comes down to whether you received the service contracted or not. In this case, the service was a reservation of ...
NL - Apologize to Monica's user avatar

Only top scored, non community-wiki answers of a minimum length are eligible