on june 17, 2014, weitzman, who had collected stamps as a child, anonymously purchased the "world's most famous stamp", the british guiana 1c magenta at a sotheby's auction in new york for $9,480,000, including buyer's premium, the highest price ever paid for a postage stamp. weitzman has since identified himself as the purchaser and has lent the stamp to the national postal museum for exhibition. in june 2015, weitzman also identified himself as the current owner of the unique plate block of four 1918 u.s. 24-cent inverted jennies, widely regarded as the world's most celebrated philatelic printing error.