http://www.snopes.com/business/taxes/woolworth.asp
There have been other cases in which numbers on mock Social Security cards have been preempted for widespread use, although none on the scale of the abuse of <NOBR>078-05-1120</NOBR>. One embarassing episode was the fault of the Social Security Board itself: In 1940, the Board published a pamphlet explaining the new Social Security program which featured an illustration of a Social Security card on its cover. The card pictured on the pamphlet bore the non-assigned number <NOBR>219-09-9999</NOBR>, and, as one might inevitably expect, in 1962 a woman presented herself to the Provo, Utah, Social Security office complaining that her new employer would not accept her SSN: <NOBR>219-09-9999.</NOBR> When the disgruntled women was informed that the SSN she had proffered was invalid and could not possibly belong to her, she pulled out her copy of the 1940 pamphlet to prove that <NOBR>219-09-9999</NOBR> was in fact the number that had been assigned to her.