ORIGINAL CONCESSION (Oct. 15, 1990). Build, operate, exploit, conserve and maintain the 33.7 km long San Luis Potosi eastern bypass. The term of the concession is 8 years 6 months.
FIRST MODIFICATION (Nov. 16, 1994). The term of the concession is extended to 30 years.
SECOND MODIFICATION (Nov. 30, 2006). The Financial Program is modified.
THIRD MODIFICATION (Nov. 30, 2007). The construction, operation, exploitation, conservation and maintenance of section 1 of 33.7 km long of the San Luis Potosi western bypass is added. The concession includes to build and conserve section 2 of approximately 6 km long of the San Luis Potosi western bypass, which is not subject to exploit. Right-of-way included. The term of the concession is modified, which expires on 10/17/2037.
FOURTH MODIFICATION (Aug. 29, 2008). Section 3 established in Annex 2 regarding the works program is added to the load; and the line is changed from southwestern, originally raised to northwestern.
FIFTH MODIFICATION (Aug. 31, 2009). Annex 2 referring to the works program and Annex 5 referring to tariffs are modified.
SIXTH MODIFICATION (Aug. 31, 2009). The term of the concession is modified, which expires on Oct. 14, 2037.
SEVENTH MODIFICATION (Feb. 26, 2020). The obligation to build, operate, exploit, preserve and maintain the 37.6km section of the highway called Ventura - El peyote is included.
EIGHTH MODIFICATION (Jan. 8, 2021). It includes the construction, operation, maintenance and upkeep of the La Pitahaya - Libramiento Ote road section. of SLP of 60.9 km A4, the Villa de Reyes Branch of 5 km A2 and complementary works.

(*) Project with Banobras and/or National Infrastructure Fund (Fonadin) involvement or support.