[manicdee]

Falsehoods like this spreading through populations that consider themselves technically literate is one reason the NIST standard requires absolute destruction.

There are methods available that will allow recovery of second, third or even fourth generation data to be recovered from magnetic disks. Writing /dev/zero "over" an SSD won't necessarily accomplish what you expect either.

[Gordonjcp]

No, there isn't.

The data is *gone*.

There is no way to recover it. If you know anything about how hard disks work, you'll see why.

There's this theoretical idea that you can get a kind of "latent image" of a mark or a space on the platter even if it's been overwritten, but hard disks haven't written things as literal north-to-south or south-to-north flips for 30 years or so. The data is written as changes of level and phase in a signal, and it's thoroughly scrambled to reduce the chances of a long run of patterns of all zeroes or all ones making the signal hard to recover.

Essentially, you'd be taking a list of floating point numbers, multiplying them all by another much smaller floating point number, adding on another floating point number, and trying to imagine what the original was.

It's not possible.

No, the NSA does not have a big magic machine that does it.

[rasz]

No one has ever demonstrated those purely theoretical methods even on an ancient very low density drive, or even a floppy drive.