As low as current 30-year rates are, 15-year rates represent an even better bargain.

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YCharts Pro, which had been listing the stock as undervalued prior to the latest drop-off, rates it an even bigger bargain now.

FORBES: Becton Selloff Is A Buying Opportunity

That could put Bristol-Myers Squibb in a weak position, allowing Icahn to bargain for an even higher price--even though it's unlikely any other big drug maker would want to purchase ImClone given the company's exclusive Erbitux deal with Bristol.

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