SDMI said it received 447 submissions to the public hacker challenge it issued in September and that it would consider the results through the week.

SDMI's statements referred to its invitation to hackers to crack six watermarking and non-watermarking technologies that it is considering as part of its specification for secure digital audio devices. The organization offered $10,000 for each successful hack.

In late October, researchers from Princeton and Rice Universities and Xerox's Palo Alto Research Center reported cracking four of the technologies in the contest. SDMI refuted their claim at the time, calling it "premature."

After SDMI's press release this week, the university group fired back, saying researchers "remain convinced" that they defeated four of the technologies in the contest and accused SDMI of focusing on eligibility for the prize, rather than whether the technology could be defeated.

The researchers agreed to forgo the cash prize in order to retain rights to publish their results, which they plan to reveal by the end of next week. As a result, they said SDMI no longer considers them to be entrants in the contest.

One company whose digital watermarking technology is among those being considered by SDMI, Blue Spike Inc. (Miami), said it submitted 130 challenges to the contest and received notification from SDMI's server that it achieved 13 successful attacks on three of the watermarks (not including its own.)

Though they aren't sure whether SDMI considers their attacks successful, Blue Spike's chief executive officer Scott Moskowitz said he is confident in the company's Giovanni digital watermarking technology as a choice for SDMI Phase II screen. But whether his company's technology is chosen or not, he said, there remain several outstanding issues. Once SDMI chooses a technology, Moskowitz said the group must hash out intellectual property issues (Blue Spike claims to hold 17 patents covering digital watermarking), licensing terms and whether consumers will voluntarily agree to use the technology.