The story
The company was formed from the merger of Indiana Gas Company (formed 1941) and Southern Indiana Gas and Electric Company (SIGECO, formed 1912). The two utilities' holding companies, Indiana Energy and SIGCORP, announced plans to merge in June 1999, and received final approval on March 9, 2000. In the fall of 2000, Vectren also acquired the natural gas distribution assets of Dayton Power and Light in western Ohio. In the fall of 2006, the company purchased Duke Energy's interest in Miller Pipeline.
It listed on the NYSE under ticker VVC in 2000.
Indiana Gas and SIGECO served as Vectren's operating companies until a 2010 reorganization saw Indiana Gas renamed Vectren North, while SIGECO was renamed Vectren South.
On April 23, 2018, CenterPoint Energy and Vectren Corporation announced they had entered into a definitive merger agreement, with CenterPoint being the emerging head company. On February 1, 2019, the merger was completed and Vectren was delisted from the NYSE. CenterPoint retained the Vectren name for Vectren's service territory until it was retired on May 3, 2021.
From Wikipedia’s article on Vectren, shared under CC BY-SA 4.0.5