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Cost basis allocation question: GM bonds conversion to stock & warrants
Because the distribution date was APR 21, 2011, THAT should be the correct date for ascertainng the stock prices of the GM stock and warrants.  The subsequent distributions after April should also be allocated in accordance with their distribution dates, with tax basis being reduced from the original APR 21st date's allocations, and reallocated to those subsequent distributions, taking into account any interim sales you might have made.