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Discussion Starter · #1 ·
I just read this question on another forum and it got me thinking. If I am selling a computer on eBay, do you think it's OK to give potential buyers the full serial number?

This guy had someone email him saying he was an Apple Tech, and wanted to use the serial to "verify" the computer. The general consensus over there was not to give it out, but I'm pretty sure that's something that people do to assure buyers the machine is legit.

I don't know, with the number of scammers out there I might be wary of giving it out, since I know of course that I'm not a scammer... but the buyer might want to clarify that...

Any thoughts on this subject?

1,889 Posts
The only really bad thing I can think of is that this person may be asking you for a valid serial number so THEY can scam someone when they try to sell a nonexistent machine.

I would tell him you'd be happy to disclose the serial number to the winning bidder upon completion of the auction, but that might be overly cautious.

Premium Member
5,247 Posts
Nearly every serial number follows a certain pattern. For example your SIN has a pattern; it's not just a random group of numbers and a partial understanding won't give you the remaining numbers (assuming they leave enough out; it's not hard to create a SIN that would be correct with 8 of 9 numbers available; the 9th digit is a check digit calculated from the other 8; all credit cards also use the rightmost digit as a check digit).

So, if my SIN is 6xxx xxx xxx anyone who knows the pattern and code can tell that I was living in Saskatchewan when I first registered for a card.

If I offer 8xxx xxx xxx then it's obvious I made the whole number up; 8 is not used as the first digit.

If I offered the first 3 digits, it is possible to calculate both the province of registration and the general date of registration, giving a clue to my age. Just as with the first digit, in the first 3 digits there are unused numbers or patterns that would clearly indicate I made the number up.

And so on.

If this guy's story was legit, then he can use that pattern to determine if it's legit number without the entire serial number.

The reasonable answer would be to offer (this is from my G4)


... or something similar; just remove 40% or so of the characters and replace them will null characters ( x in this case).

If the guy is not legit, this is useless information to him; ie it can't be used to create a valid S/N. It's not necessary to know the pattern to submit it to someone who does to verify that it appears to be a valid S/N.

Where you have a number that you think might be just a sequential number, leave the last few digits out (I used 2 in following made-up example because the example implies less than 9999 units; more than that and I would have probably left out 3, etc).

For example:

might be offered as:

As a general precaution, it's a good idea to leave the last digit out (often a check digit or character) and always at least 2 consecutive characters, preferrably 3 or more.

For an eBay sale, I would further offer to submit the entire S/N after the auction ends; although I might add conditions (perhaps a deposit, some contact info, whatever is OK with both of you).

[ February 19, 2004, 06:57 PM: Message edited by: gordguide ]
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