From DTVA website:
In April 2003, Peel Airports reached an agreement with the six local authority shareholders (Durham, Darlington, Stockton-on-Tees, Middlesbrough, Hartlepool and Redcar and Cleveland Borough Councils), to acquire a 75 percent shareholding in the Airport with the local authorities retaining a 25 percent interest in the company. In June 2010, Vantage Airport Group (formerly Vancouver Airport Services) acquired a 65 percent share in Peel Airports, which included DTVA. The six local authorities continue to be shareholders in Durham Tees Valley Airport.
On 10th February 2012, Peel Airports Limited concluded the sale of its majority shareholding in Durham Tees Valley Airport to Peel Investments (DTVA) Limited, a wholly owned subsidiary of the Peel Group.
Durham Tees Valley Airport Background Information