American Shared Hospital Services
Two Embarcadero Center, Suite 410
San Francisco, CA 94111

Tel: 415-788-5300 or 800-735-0641
Fax: 415-788-5660


American Shared Hospital Services is a publicly traded healthcare company (New York Stock Exchange AMEX symbol AMS) with a 25-year track record of leasing state-of-the-art medical equipment to hospitals and medical centers in the United States.

Through GK Financing, LLC (GKF), our majority owned subsidiary, we are the leader in Gamma Knife unit ownership with approximately a 16% market share in the United States. Our Gamma Knife model has been expanded to incorporate the financing of other technology solutions including Intensity Modulated Radiation Therapy (IMRT), Image-Guided Radiation Therapy (IGRT) and Proton Beam Radiation Therapy (PBRT).


1980: American Shared is founded by Ernest A. Bates, M.D., Chairman and Chief Executive Officer, starting as a fee-per-use mobile diagnostic imaging company. We become the second company to provide mobile CT services to hospitals.

1980 – 1991: We expand our product line to include mobile and fixed site magnetic resonance imaging (MRI), CT, ultrasound, nuclear medicine, cardiac catheterization laboratory and respiratory therapy services.

1991: Our first Gamma Knife unit opens at UCSF in San Francisco, CA.

1995: We partner with Elekta to form GK Financing, LLC (GKF) to provide alternative financing for Gamma Knife units.

1998: We sell our diagnostic imaging business to concentrate on radiosurgery, radiation therapy, and our OR21 concept.

2000: Our tenth Gamma Knife unit opens at JFK Medical Center in Edison, NJ.

2005: Our twentieth Gamma Knife unit opens at Baptist Riverside Hospital in Knoxville, TN.

2006: We enter the proton beam radiation therapy (PBRT) market by acquiring an equity interest in Still River Systems, Inc., developer of the Monarch 250, a practical, cost-efficient, single room PBRT system. In turn, we are able to contract with Tufts Medical Center in Boston, MA. for a complete radiation therapy department upgrade that includes an IMRT/IGRT as well as a single-room PBRT system.

We contract with Orlando Regional Healthcare M.D. Anderson Cancer Center in Orlando, FL on our second single-room PBRT facility.

2007: We increase our equity interest in Still River Systems, Inc.

2008: USC University Hospital in Los Angeles, CA returns to us for an upgrade to a Gamma Knife Perfexion.

We agree to provide Todd Cancer Institute at Long Beach Memorial Hospital, in Long Beach, CA with a single-room PBRT facility – our third to date.

2009: We extend our agreement with Yale-New Haven Hospital in New Haven, CT and will upgrade existing unit to a Perfexion.

We sign a letter of intent with the Todd Cancer Institute at Long Beach Memorial Hospital, in Long Beach, CA for a single-room PBRT facility – our third to date.

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