The deal was flagged up in a trading update posted by Enterprise on the London Stock Exchange.
Laine Pub Company chairman Gary Pettet said he was aiming to open six Mash Inns a year, with a target estate size of 20.
Enterprise hinted that the roll-out could begin in the next few months.
It is aiming to have ‘at least 10’ pubs trading under its partnerships such as Mash Inns by 30 September, the group said.
Although the pubs will be operated by Mash Inns, support will be provided directly from the Laine Pub Company team.
“We hope to seamlessly integrate the support for the Mash sites into our existing operational setup” said Laine’s chief executive, Gavin George.
“As existing Enterprise lessees, we are aware of the quality of the sites in their estate, so we are very excited about the depth of possibilities that this partnership presents.”
Laine Pub Company has named the new venture in honour of its first pub The Mash Tun in Brighton, which opened 20 years ago.
The Sussex-based group will also be providing ‘support and advice’ on the development of Enterprise Inn’s Craft Union Pub Company – which is expected to grow from 42 to 70 sites by October.
Enterprise Inns is the largest pub company in the UK, with around 5,000 venues nationwide.