Goldman Sachs Group has signaled it will fight a US lawsuit over subprime mortgage instruments the same way Bank of America's Merrill Lynch unit and UBS have challenged similar claims -- by invoking the concept of caveat emptor: Latin for buyer beware.

The strategy may work. By insisting that purchasers of collateralized debt obligations knew what they were getting into, Goldman Sachs is following a well-traveled path. Both Merrill and UBS won dismissal of similar claims that they misrepresented the risks of such assets by saying the buyers were sophisticated enough to know better.