Out of a field of almost 9,000 registered teams, the San Francisco-based “All Your Shreds Are Belong to U.S.” team won the $50,000 prize. Here’s a brief description of the challenge (highlighted in my Nov. 28, 2011 posting), from the DARPA Shredder Challenge page,

Today’s troops often confiscate the remnants of destroyed documents in war zones, but reconstructing them is a daunting task. DARPA’s [Defense Advanced Research Projects Agency] Shredder Challenge called upon computer scientists, puzzle enthusiasts and anyone else who likes solving complex problems to compete for up to $50,000 by piecing together a series of shredded documents.

The goal was to identify and assess potential capabilities that could be used by our warfighters operating in war zones, but might also create vulnerabilities to sensitive information that is protected through our own shredding practices throughout the U.S. national security community.

There were five puzzles in all and, as of my Nov. 28, 2011 posting, the fifth was the only one that had not been solved. By Dec. 2, 2011 all the puzzles had been solved. From the Dec. 5, 2011 news item on physorg.com,

The ‘All Your Shreds Are Belong to U.S.’ team, which won the $50,000 prize, used custom-coded, computer-vision algorithms to suggest fragment pairings to human assemblers for verification. In total, the winning team spent nearly 600 man-hours developing algorithms and piecing together documents that were shredded into more than 10,000 pieces.

…

The Shredder Challenge represents a preliminary investigation into the area of information security to identify and assess potential capabilities that could be used by war fighters operating in war zones to more quickly obtain valuable information from confiscated, shredded documents and gain a quantitative understanding of potential vulnerabilities inherent to the shredding of sensitive U.S. National security documents.

While the contest is now closed, it’s still possible to try this puzzle for fun. You can find out more about the various puzzle solutions and the winning team’s submission here.