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Health Net Leadership


Brian Ternan

Chief Executive Officer and Plan President

Brian Ternan is the CEO of Health Net of California and California Health & Wellness - one of the state's largest Medi-Cal managed care plans. With over 85,000 network providers, Health Net serves more than 3 million members. That's nearly 1 in 12 Californians. Ternan has over 30 years of leadership experience as a senior health care executive, and has been a key leader at some of the state’s largest health care plans.

Ternan assumed the role of President and CEO of Health Net California and California Health and Wellness in September 2019. Prior to joining Health Net, Ternan was a key leader Anthem Blue Cross of California and Aetna Inc. As a respected leader in the health care industry, Ternan is dedicated to improving access, and pushing for better outcomes for all Californians. Ternan is a Board Member of the Big Brothers Big Sisters of Ventura County.



Martha Santana-Chin

Medi-Cal President

Martha Santana-Chin serves as Health Net's Medi-Cal President, providing executive oversight to Health Net's Medi-Cal program. She has more than three decades of healthcare leadership experience working with independent physician practices and hospitals, federally qualified health centers, health plans, serving Medi-Cal and low-income communities. Santana-Chin, who often shares her story of growing up in extreme poverty, prides herself on understanding first-hand the struggles that many Medi-Cal enrollees face. Those challenges include food insecurity and transportation issues to homelessness and racial inequities among other social determinants of health.

Santana-Chin serves as a member of the Board of Directors of the United Way of Greater Los Angeles, is a member of the Board of Directors and Executive Committee for the Integrated Healthcare Association and is a member of the Executive Diversity and Inclusion Council for Centene. She holds a Bachelor of Science in Business Finance from California State University, Long Beach and a Master's degree in Business Administration from the University of California, Irvine.



Karen M. Johnson

Medicare Officer

Karen M. Johnson is the Medicare Officer at Health Net. Johnson leads the building of business strategies and working plans for the Medicare line of business. She has more than 30 years of leadership know-how. This includes her time as Medicare Regional President for WellCare (Arizona, California, Hawaii, Missouri and Washington). In this role, she oversaw finances, network growth and provider relations, among other duties. Johnson is a leader with a proven track record of growing programs and leading teams. These teams aim to improve the health status of at-risk populations. For instance, prior to her role at WellCare, she served as Senior Vice President of Clinical Services at Health Essentials. While in this role, she launched a clinical care model, driven by a home-based supportive care program designed to support high-risk patients and end-of-life care.

Johnson earned a Bachelor of Science degree in nursing from the University of Michigan and a Juris Doctorate from Michigan State College of Law. She also holds an Executive Certificate from the Wharton School of Business. She has served on the Board of Directors for several organizations, including The YWCA, Planned Parenthood, Jack and Jill Foundation, United Way and the American Diabetes Association. Karen also served on the Washington, D.C. Health Exchange Advisory Board.



Jennifer (Jenn) Moore

Commercial Officer

Jennifer (Jenn) Moore is the Commercial Officer for Health Net, LLC. Moore has invested 20 years into building leadership skills in her field. In her current role, Moore drives business performance, overseeing profits and losses for the Individual, Small Group and Large Group lines of business.

Moore joined Health Net in Sept 2000 as a Senior Production Support Manager. Her skills center on managed care experience in operations, sales, product management and more.

In prior roles, Moore served as Vice President of Individual Markets and Public Exchanges at Health Net. She led strategy and execution of several key programs. Her duties covered the financial and operational performance of Individual Markets in Arizona, California and Oregon.

Moore earned a Masters of Health Administration from the University of Iowa, and she holds a Bachelor of Arts degree in Humanities and Fine Arts from the University of Northern Iowa.



Kerri Balbone

Chief Operating Officer

Kerri Balbone serves as the Chief Operating Officer for Health Net, LLC. Balbone leverages her background in business growth, strategic planning and delivery innovation to serve customers. This work drives value and brings quality results. Balbone joined the company in June 2020. She brings over 25 years of health care knowledge to her oversight of all key service areas.

Prior to this role, Balbone served as COO, UnitedHealthcare Community Plan of California. She drove the company's entrance into the California market, as well as service expansion and other accolades. Balbone has broad experience managing health care delivery systems, operational strategies, IT projects and complex integrations. This was displayed at several high profile roles with UnitedHealthcare and Oxford Health Plans.

Balbone dedicates time to public service. She serves as a Public Safety Commissioner for the City of West Hollywood, California. She is also an active volunteer with the Los Angeles LGBT Center and the Los Angeles Foodbank.

Balbone earned her Bachelor of Science – Health Systems Management from University of Connecticut and her Masters of Business Administration – Health Administration from Sacred Heart University.



Garrett Leaf

Plan Chief Financial Officer

Garrett Leaf is the Chief Financial Officer for Health Net, LLC. Leaf uses his background in strategic finance, corporate management and financial analysis in this role. Leaf oversees the financial planning and actions for Health Net. He focuses on the company's financial strengths and offers actions for growth.

Leaf joined Health Net in Jan 2019 as a Chief Financial Officer. He brings an analytical and data driven approach to the company.

In prior roles, Leaf served as Plan President and Chief Executive Officer at SilverSummit Healthplan/Centene. He also served as Vice President of Finance for California Health & Wellness/Centene, from April 2014 to April 2017. Leaf applied his top-level finance experience to oversee financial performance for these positions.

Leaf served numerous youth sports organizations during his 21 years in the Greater Sacramento Region. He is a former board member of the California Capital Region chapter of the United Way. Leaf currently serves on the Board of Directors for the Greater Sacramento Urban League and the California Chamber of Commerce. He earned his bachelor’s degree in business administration from California State University, Chico.



Alex Y. Chen

Chief Medical Officer

Alex Chen is Chief Medical Officer (CMO) at Health Net, LLC. In this role, Dr. Chen leads and provides oversight of Health Net teams responsible for the Medical Affairs & Quality department. Prior to joining Health Net, Dr. Chen served as CMO at AltaMed Health Services, responsible for overall medical and utilization management. Prior to that, he held executive positions with AltaMed overseeing quality and safety. He also has taught and conducted research at Keck School of Medicine of USC as an associate professor of pediatrics, splitting his time between research and clinical activities. His major area of research interest is healthcare access and quality.

Alex earned his M.D. from Harvard Medical School, his M.S. from UCLA, and a B.A. from Northwestern University. He is board certified in pediatrics and licensed in California, where he has practiced part time since he completed his residency at UCLA.



Christy K. Bosse

Vice President, Compliance

Christy Bosse is the CA Compliance Officer of Health Net, LLC. Bosse leads the overall compliance program for the combined Health Net and California Health & Wellness health plan. Her responsibilities cover the CA market and all lines of business offered. Bosse joined Health Net in November 2004 and has since grown a vast knowledge base in fostering a culture of compliance for the company. Prior to her current role, Bosse served as the Medi-Cal Compliance Officer directly for Health Net and California Health & Wellness Medicaid lines of business. From 2008-2015, Bosse focused on compliance for Health Net's Commercial lines of business.

Bosse graduated from the University of CA, Los Angeles, earning Bachelor of Arts degrees in French and Business Administration. She also holds a Masters of Business Administration.



Darrel Ng

Vice President, Communications and Marketing

Darrel Ng is Vice President of Communications at Health Net, LLC. In this role, Darrel leads and provides oversight for Health Net teams responsible for marketing and communications on behalf of Health Net and California Health & Wellness. Darrel brings more than two decades of experience providing strategic communications counsel to political, government and corporate leaders across the country. Darrel is an expert in leading public affairs, corporate communications and marketing teams in the health care payer, provider and digital health space.

Prior to joining Health Net, he founded Fast Twitch Communications, a health care-focused strategic communications firm. He also held senior positions at W2O Group and Anthem, Inc. Darrel is a seasoned professional in the world of campaign politics and health policy. He has worked on three presidential campaigns – most recently as the Director of Vice Presidential Rapid Response for the Romney campaign in 2012. He has also served as a spokesperson for Gov. Arnold Schwarzenegger and the California Department of Insurance.

Darrel earned a BA in Political Science from UC Berkeley, and is based in Sacramento.



David Koenig

Vice President of Government Relations, Public Affairs & Community Investments

David Koenig is Vice President of Government Relations, Public Affairs & Community Investments at Health Net, a subsidiary of Centene Corporation. With a portfolio of community, political, and infrastructure investments, Mr. Koenig oversees a diverse statewide team of staff and consultants. They work at the state and local level to improve Health Net's ability to provide high-quality health care services through engaging community and government entities.

Prior to Health Net, David advised Centene Corporation in California for over ten years as the principal at his consulting firm, Koenig Consulting LLC. His firm specialized in policy advocacy, strategy development and implementation, community engagement, multi-level government relations, political campaigns, coalition building, and philanthropic solicitation. Mr. Koenig served as a senior strategist, campaign, and coalition building manager to corporate, non-profit, pro-bono, and labor clients on legislative advocacy and community engagement campaigns.

David holds a Bachelor of Arts degree in Political Science with a Minor in Religious Studies from California State University at Northridge and serves on volunteer boards, past and present, including: Californians for the Support of Early Education, and the PTO at his kid's elementary school.

Last Updated: 09/20/2021