The recent disclosure that personal information about 198 million U.S. voters had been left unprotected on the internet made plenty of headlines. At least one lawsuit against the company responsible has already been filed, and the incident serves as a warning to other "Big Data" collectors that they need to protect personal information more carefully.
But it could have been so much worse. The registered voters' names, addresses, party registration and voting history that were part of the database are public records in many states. Crucially, no Social Security numbers or financial-account information were included. Potentially the most sensitive type of information included was individual voters' birthdays.
So what kind of personal information matters in a data breach? What do you need to worry about, and what can you afford to make public?
The four pieces of information most useful to a criminal seeking to steal your identity are your full name, including your middle name if you have one; your current address; your date of birth; and your Social Security number (or Social Insurance Number in Canada). Let's go over how — and whether — to protect each one.
The short form of your name — for example, "Will Smith" — is generally known to all your acquaintances, and many others. There's not much you can do about that, and you should feel safe giving out the short form of your name.
But how many people know your full legal name — e.g., Wilberforce Susquehanna Smith IV? That's what you need to open bank accounts, get a car loan or buy a house. It's probably also on your driver's license, marriage certificate and birth certificate, which are public records. But that doesn't mean you have to tell your full legal name to strangers or put it on your Facebook page.
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Full names are powerful. They let you tell one individual apart from another. That's why famous assassins such as Lee Harvey Oswald and James Earl Ray often seem to have three names: Authorities use their full legal names to distinguish the assassins from innocent people with similar names.
To protect your full legal name, don't tell people your middle name or your true first name if you use a nickname. Limit the number of people who know your full name to those who really do need to know it — and don't put a picture of your driver's license or passport online.
An address is also a matter of public record. It's a bit harder to get a stranger's address these days now that people don't use phone books anymore, but a quick Google search will usually turn it up.
Your address is also printed on every piece of snail mail you receive — and throw out. You can try ripping the address label off recycled magazines and tearing up junk mail (I do), but overall, protecting your address may be futile. This cat, as they say, is out of the bag.
Date of birth
This is where it gets interesting. Like a full name, your date of birth is on your driver's license and passport, but you do NOT need to give it out. Who really needs to know it besides your family and close friends?
Don't make your date of birth public on Facebook. Don't even include the month or day, because anyone can guess your year of birth by checking the Facebook pages of your high-school friends. Go ahead and have a birthday party, but tell anyone who asks that your birthday was "a couple of weeks ago."
Social Security/Insurance number
This is the big megillah. You do NOT want to give your Social Security number or Social Insurance Number to anyone who doesn't need to know it. And that circle should be limited to your employer, your spouse and any company with which you have a financial account.
Your doctor's staffers, despite what they may insist, do not need to know your Social Security number. Give them your medical-insurance ID number instead and tell them to look up the regulations.
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Don't carry your Social Security card or Social Insurance Number card in your purse or wallet. Memorize the number instead, and lock the card in a safe place.
If someone gets your Social Security number, and then gets your name, address and date of birth from public sources or from Facebook, they can do pretty much anything while posing as you — get a job, buy a house, get arrested, pay taxes, get your tax refunds. A Social Security number or Social Insurance Number is the golden key to identity theft.
This isn't to say that identity theft doesn't happen without a Social Security number. It does. But having your Social Security number or Social Insurance Number floating around just makes it so much easier.
Illustration: Shutterstock/Tom's Guide