Investment Management

Company Profiles

John N. Mayberry

Chairman and Chief Investment Officer

Jack Mayberry has been the Chairman and Chief Investment Officer of Core Asset Management Company since 1986. Before joining Core, Jack practiced law at Cravath, Swaine & Moore, a New York corporate law firm and specialized in anti-trust and securities litigation. He is a member of the bar of the State of New York. Jack received a BA with honors in Greek and Latin from Swarthmore College and earned a JD from Yale Law School.

He has been a member of the board of Planned Parenthood of New York City (PPNYC) since 1991, co-chair from 1995-1997 and Treasurer and Secretary from 1997-1998. Since 1998, he has been a member of the investment committee, which oversees PPNYC's endowment. From 2002 to 2009, he served as chair of that committee. Jack is a member of the board and former chairman of Video Volunteers, a not-for-profit organization that provides access to media for the world's marginalized people. It is active in India and is expanding the scope and breadth of its work ( and

From 1994 until 2008, Jack was a member of the board of the Spoleto Festival USA, a performing arts festival in Charleston, South Carolina, and served on the Finance and Investment Committees.

Jack is now an Honorary Board Member of  PPNYC.


Margo Dillon Leardini

Margo has been with Core Asset Management Company since 2005.

Previously, Margo was the Assistant Director of Admissions/Coordinator of International Recruitment at Dominican University of California, from 2001-2005. From 1999-2001 she was the Director of Private High School Placements for Face the World Foundation, a non-profit that facilitates educational and cultural exchange experiences for young people from around the world.

From 1995-1999 Margo lived, worked, and studied in Europe, spending time as an intern. at Carpenter Bowring, an Insurance Brokerage House, in London, England (1995-1996) a private English Teacher/AuPair in Madrid, Spain (1996-1997) and obtaining a certificate in Translating (French Language) in Paris and Nice, France (1997-1999)

Margo received her B.A. with honors in English from St. Mary's College, Notre Dame, Indiana, in 1995 and spent her Junior year studying in Florence, Italy with Gonzaga University.

Margo is a member of Alliance Francais, and Toastmaster's International.