The title was enacted into positive law by
Pub. L.Tooltip Public Law (United States)95–473, § 1, October 17, 1978, 92
Stat.1337;
Pub. L.Tooltip Public Law (United States)97–449, § 1, January 12, 1983, 96
Stat.2413; and
Pub. L.Tooltip Public Law (United States)103–272, July 5, 1994, 108
Stat.745 (subtitles II, III, and V-X)
During the time between when the Title 49 positive law codification began in 1978 and when it was completed in 1994, the remaining non-positive law sections were placed in an appendix to Title 49.[1][2]
In 2010, Congress enacted
Title 51 as a new positive law title concerning
NASA and commercial space programs. As part of the codification, the heading of Subtitle IX was marked "transferred" and the contents of such subtitle were moved to Title 51.[4] Five years later, the
FAST Act inserted a new Subtitle IX. The heading of new Subtitle IX was given the heading "Multimodal Freight Transportation."[5]
^Fixing America's Surface Transportation Act,
Pub. L.Tooltip Public Law (United States)114–94 (text)(PDF), Sec. 8001(a), 129
Stat.1312, 1604; Act of 2015-12-4.