LexisNexis completed their efforts in late 2006 (covering 1789-1969). LexisNexis rescanned the maps in the set via a partnership with the University of Maryland, College Park.
The historical map collection was completed by LexisNexis in late 2006, covering the years 1789 to 1969.  They partnered with the University of Maryland, College Park to re-scan the maps for improved accuracy and accessibility.