Our Team

As a client, you’ll be supported by a team of experts who are dedicated to helping you achieve your financial goals. Client service is of utmost importance to us.

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William Tanner

Co-Founder and Chairman, Co-Equity Portfolio Manager

William Tanner, Co-Founder, Chairman, Equity Co-Portfolio Manager

Bill Tanner is the Chairman and Co-Equity Portfolio Manager of AMI Asset Management. He Co-Founded the firm in 1994, has been the portfolio manager since the inception of the firm and is still a member of the firm’s Investment Committee. Mr. Tanner began his career in public accounting auditing small and medium-sized companies before co-founding the CPA/Business Management firm Tanner Mainstain Glynn & Johnson in 1975. He earned a degree in Business Administration and Accounting from the University of California, Los Angeles and a Master’s Degree in Taxation. Mr. Tanner is a shareholder of the firm. He is also a longtime board member of the UCLA Jonsson Cancer Center Foundation.

[email protected]

(424) 320-4001

BIO

Peter Mainstain

Partner

Peter Mainstain, Partner

Peter Mainstain, CPA is a shareholder of the firm. He has been a practicing Certified Public Accountant since 1972 and has extensive experience in all phases of the entertainment and sports industries, including personal business management as well as financial and retirement planning. Mr. Mainstain co-founded the CPA/Business Management firm Tanner, Mainstain, Glynn & Johnson in 1975, which is now part of Ground Control Business Management. Mr. Mainstain holds a Bachelor of Science in Business Administration and Accounting from California State University, Northridge, and has done post-graduate study at USC and Golden Gate University. He has taught at UCLA Extension and has been a guest lecturer at industry and professional organizations. Mr. Mainstain is a member of the American Institute of Certified Public Accountants as well as the California Society of Certified Public Accountants.

[email protected]

(424) 320-4000

Bio

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Matthew Humiston

President

Matthew Humiston, President

Matt Humiston is responsible for running the day-to-day operations of AMI. When Mr. Humiston joined the firm in 2000, he and Bill Tanner formulated the investment process that AMI uses today. Mr. Humiston oversees the portfolio management trading and reporting operations. Prior to joining AMI, Mr. Humiston worked at internet startup Pop.com and at Brillstein-Grey Entertainment. He earned a Bachelor of Arts in Economics degree from the University of California, Santa Barbara. He also received a professional designation in Personal Financial Planning (PFP) at the University of California, Los Angeles in 2005. Mr. Humiston is a shareholder of the firm.

[email protected]

(424) 320-4002

BIO

Christian Sessing, CFA

Chief Investment Officer, Lead Equity Portfolio Manager

Christian Sessing, CFA, Chief Investment Officer, Lead Equity Portfolio Manager

Christian Sessing leads the equity research efforts for the firm and is responsible for the portfolio construction for all of the firm’s equity strategies. He began his career as an Equity Analyst with a regional brokerage firm and then spent 5 years at Crowell, Weedon & Co. He earned a Bachelor of Business Administration with a concentration in Finance from California State University, Northridge. His professional and business activities consist of being a member of the CFA Institute. Mr. Sessing has been with the firm since 2005 and is a shareholder.

[email protected]

(424) 320-4004

BIO

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Katharine Kim

Chief Compliance Officer

Katharine Kim, Chief Compliance Officer

Katharine Kim is responsible for the day-to-day implementation and maintenance of the firm’s compliance program to ensure compliance with all industry regulations. Mrs. Kim coordinates all the audits at the firm, including the annual GIPS audit. She also oversees the daily management of client accounts and the the administration of new accounts. Mrs. Kim began her career performing client services duties at Dreyfus Brokerage Services. She earned a Bachelor of Arts in Economics degree from the University of California, San Diego. Mrs. Kim has been with the firm since 2002 and is a shareholder.

[email protected]

(424) 320-4003

BIO

Andrew Zamfotis, CFA

Co-Equity Portfolio Manager

Andrew Zamfotis, CFA, Portfolio Manager

Andrew Zamfotis is responsible for assisting in all phases of the equity research process. Prior to joining AMI, Mr. Zamfotis was a Senior Analyst at EVA Dimensions, an equity research firm focused on economic profit-based models whose clients manage over $100 billion. Prior to EVA, he was a senior analyst at the long/short hedge fund Legarde Capital Management. Mr. Zamfotis began his career at the Halyard Capital Fund, a private equity fund where he was responsible for the Fund’s investments into Technology, Media, Internet, and Telecommunications companies. He holds a Bachelor of Science in Finance and Information Systems degree from New York University’s Stern School of Business where he graduated with honors. He is a CFA® Charterholder and has been with the firm since 2015. Mr. Zamfotis is a shareholder of the firm.

[email protected]

(424) 320-4012

BIO

Richard Schimbor, CFA

Senior Equity Analyst

Richard Schimbor, Equity Analyst

Richard Schimbor is responsible for assisting in all phases of the equity research process, including model construction, news and event tracking, and research projects. Mr. Schimbor began his career at Falcon Point Capital, a long short hedge fund in San Francisco. Most recently Mr. Schimbor served as an Assistant Vice President at U.S. Bancorp. Richard has held internships in equity research with Trust Company of the West and Dalton Investments. Mr. Schimbor received a B.A. in Economics with Highest Honors from the University of California, Berkeley and an M.B.A from the UCLA Anderson School of Management. Mr. Schimbor is a CFA® Charterholder and has been with the firm since 2016.

[email protected]

(424) 320-4008

BIO

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Andrhe Cunha

Equity Analyst

Andrhe Cunha, Equity Analyst

Andrhe Cunha is responsible for assisting in all phases of the equity research process, including model construction, news and event tracking, and research projects. Mr. Cunha began his career as an Equity Research Intern at Wedbush Securities, a privately held investment firm based in Los Angeles. Mr. Cunha received his B.S. in Business Administration with Highest Honors from the Marshall School of Business at the University of Southern California. Mr. Cunha has been with the firm since 2023.

[email protected]

(424) 320-4005

BIO

Daniel Schniedwind, CFA

Managing Director - Fixed Income

Daniel Schniedwind, Managing Director - Fixed Income

Daniel Schniedwind is responsible for managing the firm's tax-exempt, taxable and high yield fixed income strategies. Prior to joining the firm, Mr. Schniedwind was a Senior Credit Analyst at Denver Investments for 5 years. Mr. Schniedwind started his career as a Credit Analyst/Portfolio Assistant at AMI Asset Management. He earned a Masters of Science degree in Finance from Indiana University and a Bachelors of Arts degree in Economics from Whittier College. Mr. Schniedwind is a CFA® Charterholder and rejoined the firm in 2019.

[email protected]

(424) 320-4006

BIO

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Matthew Dorband

Director of Sales and Marketing

Matthew Dorband, Director of Sales and Marketing

Matt Dorband leads the marketing and sales efforts of the firm. He is responsible for developing and executing the firm’s business development plan for promoting the equity strategies within the institutional investment community. He previously spent 13 years in the commercial real estate industry at CB Richard Ellis and Colliers International focusing on assisting businesses with corporate real estate planning. Mr. Dorband earned a Bachelor of Science in Business Administration degree with an emphasis in Finance and Entrepreneurship from the University of Arizona. Mr. Dorband has been with the firm since 2012.

[email protected]

(424) 320-4007

BIO

Andrew Wood

Head of Advisory Distribution

Andrew Wood, Director, Head of National Accounts

Andrew Wood leads the Broker-Dealer Client Coverage for the Firm. Prior to joining AMI, Mr. Wood spent 11 years at Morgan Stanley where he was most recently a Partner and the Chief Operating Officer for The Gage Group, a boutique family wealth advisory group based in Morgan Stanley’s Beverly Hills Office. Before that, Mr. Wood served as the Business Development Manager for Morgan Stanley’s Beverly Hills, Westwood and Santa Monica Offices. Mr. Wood began his career as an Equity Product Specialist for Morgan Stanley in New York City. Andrew graduated from Columbia University with a Degree in Economics. During his time at Columbia, he was also a four year-member of the Men’s Varsity Swim Team. He remains actively involved in his alma mater as a Board Member of Columbia’s Young Leaders Council, Young Alumni Board and Club of Southern California. Mr. Wood has been with the firm since 2024.

[email protected]

(424) 320-4015

BIO

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Erin Gudino

Operations Associate

Erin Gudino, Operations Associate

Erin Gudino assists in the daily management of client accounts and administration of new accounts. Mrs. Gudino previously worked as an administrative assistant at KPMG LLP in Boston. She earned a Bachelor of Arts in Media Studies degree from Sacred Heart University. Mrs. Gudino has been with the firm since 2010.

[email protected]

(424) 320-4011

BIO

Christopher Guerrero, CISO

Equity Trader, IT

Christopher Guerrero, Equity Trader, IT

Christopher Guerrero is responsible for managing AMI’s IT operations, as well as assisting with equity trading and coordinating proxy voting. Previously, Mr. Guerrero worked at Tanner, Mainstain, Glynn & Johnson for 17 years as the IT Director. He received a Bachelor of Sciences in Psychology and Political Science degree from the University of California, Los Angeles. Mr. Guerrero has been with the firm since 2014.

[email protected]

(424) 320-4010

BIO

Andrew Kim

Equity Trader, Operations Associate

Andrew Kim, Equity Trader, Operations Associate

Andrew Kim is responsible for implementing the equity trading for AMI. He also assists in the daily management of client accounts, the maintenance of the performance composites and the annual audits. Previously, Mr. Kim worked in the technology sector and later transitioned into an operational role in renewable energy. He received his Bachelor of Science in Theoretical and Mathematical Physics from the University of Washington. Mr. Kim has been with the firm since 2025.

[email protected]

(424) 320-4009

BIO