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GRK’s mission is to provide high quality services and lead organizations involved in the insurance industry to success, to provide these services with diligence, integrity, and accountability, to encourage an atmosphere of partnership with and mutual respect for all organizations or individuals with whom we do business, to support our employees in ways that empower them to achieve their highest potential.

Underwriting for over 150 years

Who We Are

We are a group of professionals in the exciting field of insurance and risk management.  Our job is providing management and administrative support to persons and organizations in exploiting opportunities and meeting challenges in this area.  Therefore, this is a broad and diverse endeavor, as risk and opportunity are much a part of human economic experience.  The pursuit of our discipline requires the collaboration of employees with a wide range of background and experience.  This necessity for collaboration provides a uniquely wide range of career opportunity, both professional and semi-professional, both technical and managerial.

G.R. Klinefelter Underwriters, Inc. is the managing general agency for several Lancaster County-based Insurance companies.  Our largest subsidiary is Windsor-Mount Joy Mutual Insurance Company, which currently holds an A (Excellent) rating by A.M. Best, as well as Cloister Mutual Casualty Insurance Company.

Our History

GRK began as an independent insurance agency in the 1930’s. In 1964, the organization developed into a management company that currently serves two mutual insurance companies, and in the past has managed a vast array of insurance related organizations. Finally, GRK has managed and continues to manage special insurance situations for other companies or associations.

One of the companies that we currently manage is Windsor Mount Joy Mutual Insurance Company.  WMJ has been in business since 1844, and is a result of numerous mergers, acquisitions, and consolidations over the last 150 years.

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Another company we currently manage is Cloister Mutual Casualty Insurance Company, which was formed in 1961.  It was created by a mutual benefit association wishing to become an insurance company to further benefit its members.  Presently, it is the result of consolidations with other similar associations and insurance companies.

A Legacy Looking to the Future

As a family-owned company, G.R. Klinefelter has strong and lasting roots in the Lancaster County community. The building that houses the company headquarters in downtown Ephrata has been in the Klinefelter/Cox family since the 1800s and once housed the Cox Drug Store. In the 1950s, George R. Klinefelter started his insurance business as an agent for Windsor Mutual in the basement of his family’s drugstore, offering a variety of insurance products including boat insurance, which satisfied his personal passion for boating.

But, today’s GRK doesn’t just rest on its rich history; instead, we continually strive to do business with a progressive and innovative eye towards the future.

Our Core Values

IntegrityAccountabilityPerseveranceDiversityCommunityCommitment

Partnerships