The Leeds- and City of London-based crisis, thought leadership and behaviour change specialist was set up by Bennett and Simon Maule.
Bennett previously owned 45 per cent of the business, but has now sold his shares to the business for just under £116,000, documents filed at Companies House show.
Bennett said he would be "exploring some exciting new projects and making time for the family".
The firm is now majority-owned by Maule, with director Keith Brookbank in possession of a minority stake.
The firm has 10 staff and a network of associates, which now includes Bennett. Another associate is former Parole Board comms head Tim Morris.
Maule said: "Both I and the team are hugely grateful for everything Jon has done at Linstock, and will continue to seek his input on future projects. We also look forward to building on the strong foundations built over the last decade to create a new chapter in Linstock’s story."