The USPTO is fast approaching another milestone... Patent number 8,000,000 might be less than a year away. The highest numbered utility patent (as of Oct. 19, 2010) is 7,818,816. At the current rate of about 60,000 patents per quarter, the USPTO could reach the 8 million mark as early as next August or September.
Patent 7,000,000 was issued on February 14, 2006 to American chemical company Dupont for a new type of polysaccharide fiber. Patent 7,500,000 was issued on March 3, 2009 to IBM.