Markel Corporation, a Virginia-based specialty insurer, has agreed to acquire Thompson Insurance Enterprises (THOMCO), a privately held program administrator underwriting multi-line, industry-focused insurance programs.

Georgia-based THOMCO manages more than 20 national programs including medical transportation, senior living, childcare centers, fitness clubs, pest control operators, tanning salons and inflatable rental operators, among others.

THOMCO expects to underwrite in excess of $170,000,000 in gross written premium in 2011.

THOMCO will operate as a separate business unit with its chairman Greg Thompson and president Bob Heaphey leading the operation which will be a part of Markel Specialty.

Markel president and co-COO said that with the acquisition they are witnessing the combination of two companies that share a similar history.

The transaction is expected to complete in the first quarter of 2012 subject to customary closing conditions, including Hart-Scott-Rodino clearance.

Terms of the transaction were not disclosed.