BERKELEY (CBS 5) – A team of University of California researchers has found what may be the best solution so far to spam. They are trying to convince U.S. Banks not to process transactions with three overseas banks overwhelmingly favored by spammers.

After spending years analyzing nearly a billion messages and making about 150 purchases to try to learn the spam “trajectory,” the team discovered that 95 percent their spam transactions were processed by just three financial institutions:  Azerigazbank in Azerbaijan, DNB Nord in Denmark,  and St. Kitts & Nevis Anguilla National Bank in theWest Indies.

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“These tend to be high risk transactions and there’s fewer banks that want to deal with high risk transactions,” said researcher Nick McCoy.

Chris Kanish of theUniversityofCalifornia San DiegosaidU.S.banks could help sever the spam link by refusing to accept transactions with those banks.

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“You basically say ‘if this is a western customer that’s making a pharmaceutical purchase to one of these problem banks that we know is harboring spam, we don’t want that (purchase) to go through,’”  Kanish told ConsumerWatch.

The researchers said they have approached Visa, but have yet to hear back from the credit card company.

The team presented the findings in a Symposium on Security and Privacy inBerkeley, May 22-25.

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