Data is stored as magnetized bits on a disk, with north and south representing our two forms of data (ones and zeroes), right? The problem is that we can't perfectly flip poles in any particular bit, and there will be some residual traces of what the bit used to be such as a weaker magnetic pull, fine-grained imperfections, and other forensic factors. So we can use those different pieces of data to figure out what bits were one, two, and even more overwrites in the past (with increasing difficulty every overwrite).
I'm not familiar with similar forensics on Solid State Drives, but I could look into it if you want me to.
The "Overwriting Hard Drive Data: The Great Wiping Controversy" paper published 2008 claims you are wrong.
You can easily find a copy on google-scholar with the help of sci-hub.
To quote: "The purpose of this paper was a categorical settlement to the controversy surrounding the misconceptions involving the belief that data can be recovered following a wipe procedure. This study has demonstrated that correctly wiped data cannot reasonably be retrieved even if it is of a small size or found only over small parts of the hard drive. Not even with the use of a MFM or other known methods. The belief that a tool can be developed to retrieve gigabytes or terabytes of information from a wiped drive is in error. [...] Further, there is a need for the data to have been written and then wiped on a raw unused drive for there to be any hope of any level of recovery even at the bit level, which does not reflect real situations. It is unlikely that a recovered drive will have not been used for a period of time and the interaction of defragmentation, file copies and general use that overwrites data areas negates any chance of data recovery. The fallacy that data can be forensically recovered using an electron microscope or related means needs to be put to rest."
Even then, it can be restored with great effort. They likely won't do that.
Please ... enlighten me ... I'm 99.9% certain YOU CAN'T restore shit if you overwrite it.
Data is stored as magnetized bits on a disk, with north and south representing our two forms of data (ones and zeroes), right? The problem is that we can't perfectly flip poles in any particular bit, and there will be some residual traces of what the bit used to be such as a weaker magnetic pull, fine-grained imperfections, and other forensic factors. So we can use those different pieces of data to figure out what bits were one, two, and even more overwrites in the past (with increasing difficulty every overwrite).
I'm not familiar with similar forensics on Solid State Drives, but I could look into it if you want me to.
The "Overwriting Hard Drive Data: The Great Wiping Controversy" paper published 2008 claims you are wrong.
You can easily find a copy on google-scholar with the help of sci-hub.
To quote: "The purpose of this paper was a categorical settlement to the controversy surrounding the misconceptions involving the belief that data can be recovered following a wipe procedure. This study has demonstrated that correctly wiped data cannot reasonably be retrieved even if it is of a small size or found only over small parts of the hard drive. Not even with the use of a MFM or other known methods. The belief that a tool can be developed to retrieve gigabytes or terabytes of information from a wiped drive is in error. [...] Further, there is a need for the data to have been written and then wiped on a raw unused drive for there to be any hope of any level of recovery even at the bit level, which does not reflect real situations. It is unlikely that a recovered drive will have not been used for a period of time and the interaction of defragmentation, file copies and general use that overwrites data areas negates any chance of data recovery. The fallacy that data can be forensically recovered using an electron microscope or related means needs to be put to rest."