Our History

Founder / Former Agency Owner: Rick Gross

Rick graduated locally from Alter High School (Kettering, Ohio) in 1977. He went on to the University of Dayton and graduated with a degree in Business Management in 1981.

Rick entered the insurance world in 1984 as an insurance adjuster. After 3 years working as an adjuster, he joined Group 3 Insurance (the predecessor of Gem City Insurance Agency).

In 1996, Rick left Group 3 to start Gem City Insurance Agency, Inc. In 1999, along with a partner, he came back and bought Group 3 Insurance. In 2004, the agency was renamed Gem City Insurance Agency, Inc.

Rick was a member of several organizations throughout the years:
• Centerville Noon Optimist – Board of Directors, President (1991), Optimist of the Year
• First Steps Foundation – Board of Directors

Rick passed away in November, 2014.


Current Owner: Ron Tinnerman, CIC

Ron joined the family owned Tinnerman Insurance Agency in 1990 after graduating from Centerville High School in 1986 and Miami University in 1990 with a degree in Business-Finance. Ron became owner of Tinnerman Insurance in 2001 upon the retirement of Dave Tinnerman Tinnerman Insurance acquired Gem City Insurance in July of 2015 and merged the operations of the two agencies in the fall of 2015. Ron currently serves as President and Principal of both agencies. Ron earned in 1995 and still holds today the “Certified Insurance Counselor” or “CIC” professional designation. Ron is active locally in the Centerville Noon Optimist Club, The Optimist 2.0 Club, and the South Dayton American Business Club. Ron resides in Centerville with high school sweetheart and wife of over twenty-five years; Jill. Ron and Jill have two sons.