TC Energy (formerly TransCanada) acquired Columbia Pipeline Group from NiSource in 2016. Please follow TC Energy on LinkedIn here: https://www.linkedin.com/company/tcenergy/
NiSource (www.nisource.com) retained ownership its local distribution companies, including:
o Columbia Gas of Massachusetts
o Columbia Gas of Pennsylvania
o Columbia Gas of Ohio
o Columbia Gas of Maryland
o Columbia Gas of Virginia
o Columbia Gas of Kentucky