In another blog last week, Moussouris said that the quantity and quality of the entries -- up to at that point only 10 -- had "exceeded our expectations."
She did not name the participants, but did say that they included security researchers "with great track records," individuals or teams from academia, and others.
From her account, most contributors worked close to the April 1 deadline: Half of the 20 total submissions were filed in the last nine days of the contest, and one squeezed in under the wire with just nine minutes to spare last Saturday.
In fact, Microsoft rejected a submission that missed the deadline by just eight minutes. Moussouris cited "fairness to the others" as well as Washington State contest rules as the reasons why the company wouldn't bend.
Although there's virtually no chance that anything Microsoft receives from BlueHat Prize could make it into Windows 8 -- this year's upgrade will likely reach the "release to manufacturing" milestone just weeks after the contest winners are revealed -- the company could roll some of the technologies into a Windows 8 service pack next year, Storms said in a 2011 interview when BlueHat Prize debuted.
Microsoft has done something similar in the past: In mid-2004, it revamped Windows XP's security with Service Pack 2 (SP2).
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, or subscribe to Gregg's RSS feed. His email address is email@example.com.
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