A DARPA challenge to reconstruct shredded documents has been won, two days before the deadline. The winning team, All Your Shreds Are Belong To U.S., developed an algorithm that looked for similar edge shapes or marks on the fragments, then suggested potential matches for any given piece. Finally, a human team tested the solutions. Using this system, they reconstructed five documents shredded into over 10,000 pieces in order to crack Spy vs. Spy-themed puzzles embedded within them. Their full solutions, along with other documents, can be found on the Shredder Challenge site.

The challenge was meant to give the U.S. military better ways to read shredded enemy documents, and to identify weaknesses in their own security practices. The success of the team comes as a surprise, says the director of the DARPA Information Innovation Office, since "lots of experts were skeptical that a solution could be produced at all let alone within the short time frame."

According to the winners, however, this achievement hardly makes document shredding obsolete. The group spent about 600 man-hours developing the algorithm and assembling the pieces into a total of seven pages, far less than the contents of an average shredder bin. They found the process "not easy at all," member Otavio Good told New Scientist. "I don't think you have much to worry about with your shredded documents."