unshredding

In some cases it is technically possible to reassemble the pieces of shredded documents; the feasibility of such a project is a benefit calculation. If the chad is not further randomized, the "noodles" that belonged to the same document tend to come out of the shredder close to each other and remain roughly in that configuration. Furthermore, when the documents are fed to the shredder in a way that the lines of text are not perpendicular to the shredder blades, portions of text may remain legible on the strips.
If the shredder doesn't cut paper small enough, confidential documents could be removed from the trash, reassembled and read by criminals. This can lead to corporate espionage as diving is the easiest way for professional thieves to steal sensitive information from businesses. That's why several new shredders provide protection from information theft by cutting paper into pieces significantly smaller than the length of a staple.
These micro cut shredders make it difficult for criminals to assemble a document by cutting a piece of paper into about 3,770 bits vs. the average confetti cut shredder, which cuts a piece of paper into 300 pieces or the average strip cut shredder, which cuts a piece of paper into 34 strips.

Information provided by www.securityconsole.co.uk