Open Field Capital seeks to capture alpha from the market dislocations that result when rapid technological innovation occurs. The greatest investment opportunity exists where the emergence of a new technology creates an entirely new market, an open field.

Open Field’s opportunity to invest in technological innovation broadens as technology proliferates more of our economy. Underlying the rapid disruption that ensues are powerful, long term and evolving trends in technology, such as mobile computing, virtual / cloud computing and artificial intelligence.

These ‘megatrends’ are both self-reinforcing and convergent. Combined, they provide the framework of Open Field’s investment strategy as we search for public and private companies that can sustain rapid growth and create enduring franchise value.


Open Field Capital LLC was established in August of 2003 with the exclusive focus of managing emerging technology portfolios of public equity and venture investments. It is Open Field Capital’s core philosophy that disruptive technologies are the best driver of sustained equity out performance.

The founding principals of Open Field Capital have worked together for over 18 years and have a substantial depth and breadth of experience in the financial markets. Throughout that time, the principals have worked in emerging technology markets and have developed both an investment philosophy and methodology tailored to the sector's unique characteristics.


Marc Weiss

Chief Investment Officer

MARC WEISS is the Open Field Chief Investment Officer and a member of its three person Investment Committee. Mr. Weiss joined Open Field full time in 2005. Mr. Weiss joined Amerindo Investment Advisors Inc. in 1994 and became its Director of Research in 2002 as well as serving as one of five members of its Investment Committee. Prior to joining Amerindo Mr. Weiss was a Senior Associate Engineer with IBM between 1989 and 1992 where he authored 2 patents (5670018 and 6258497). Mr. Weiss is a founding member of Open Field Capital LLC. Mr. Weiss holds a B.S. in Electrical Engineering from Rensselaer Polytechnic Institute, an M.Eng. in Electrical Engineering from Cornell University, and an M.B.A. from Columbia University.

James Stableford

Director of Portfolios
Chief Compliance Officer

JAMES P.F. STABLEFORD is the Open Field Director of Portfolios, Chief Compliance Officer, and a member of its three person Investment Committee. He began his career in 1985 with Prudential Bache Securities in London, where he served for a year as a broker's assistant until moving to Cigna International Investment Advisors, where he served in operations and as a portfolio assistant from 1986 through October 1987. From 1989 until joining Open Field full time in 2003, he served in operations and portfolio management for Amerindo Investment Advisors UK Ltd and was one of five members of Amerindo's Investment Committee. Mr. Stableford is a founding member of Open Field Capital LLC. Mr. Stableford holds a BSc in Economics from Brunel University in Middlesex.

Michael Sandifer


MICHAEL J. SANDIFER serves on Open Field’s three person Investment Committee. His financial career began at Brown Brothers Harriman in 1970; later moving to Baker Weeks & Co. In 1976 Mr. Sandifer became a Vice President of Reynolds, which merged with Dean Witter. Next at Donaldson Lufkin and Jenrette, in 1982 he became a Partner and then a Principal at Woodman Kirkpatrick & Gilbreath, later acquired by Hambrecht & Quist. In 1990 Mr. Sandifer joined Amerindo Investment Advisors Inc., serving on Amerindo’s five member Investment Committee. He became Chairman of UM Autonomous Systems Limited in April 2021. He is a founding member of Open Field Capital LLC; joining full time in 2005. Mr. Sandifer holds a B.A. in Economics from Occidental College and a J.D. from the University of California, Los Angeles.



(as of December 31st 2020)


Since 2005, Open Field Capital has managed long only portfolios of high growth publicly traded stocks in the emerging technology sector.

Open Field's long only clients include institutional investors, family offices and high net worth individuals. Open Field's success comes from combining the mantra of buy and hold with a proactive management of cash weightings. This strategy has enabled Open Field to exploit the buying opportunities provided by the stock price volatility of fast growing emerging technology companies.


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