NEW YORK (Standard&Poor's) Jan. 13, 2004--Standard&Poor's Ratings Services assigned its 'B' rating to Iron Mountain Inc.'s proposed £125 million senior subordinated notes due 2014. Net proceeds will be used to acquire Mentmore PLC's 49.9% stake in Iron Mountain Europe Limited (IME), a majority owned unit of Iron Mountain, and for general corporate purposes. The transaction will help hedge the company's investment in the United Kingdom. At the same time, Standard&Poor's affirmed its existing ratings, including a 'BB-' corporate credit rating, on the company. Boston, Mass.-based records management company had total debt outstanding of $2.06 billion outstanding at Sept. 30, 2003. The rating reflects the company's relatively high debt leverage, limited debt capacity for another