TriVest VCT has sold Secure Mail Services, the Northampton-based provider of business mail solutions with 550 staff, to Candover for £4.2m. TriVest will also receive a further £1.5m over the next three years conditional on the renewal of one of Secure Mail's key contracts. Founded in 1991 as a secure delivery service for credit cards, Secure Mail now delivers a range of sensitive documents on behalf of institutions such as high street banks, ticketing agencies and the Passport Office. Candover also recently acquired DX Services, and the two companies will be merged to create a combined secure delivery business.