Our Leadership

Larry Renfro

Chief Executive Officer

Larry Renfro is chief executive officer of Optum, UnitedHealth Group's health services platform, overseeing OptumInsight, OptumHealth and Optum Rx. Renfro joined the company in January 2009 and has served as chief executive officer of the public and senior markets group. He worked in the office of the CEO at UnitedHealth Group coordinating projects in new areas of growth and development.

Renfro was formerly a senior executive officer at Fidelity Investments and a member of the Fidelity Executive Committee. He was president and chief executive officer of AARP Services, Inc., before he rejoined Fidelity in 2008. Renfro has also held senior executive positions at NewRiver, Inc.; State Street Bank & Trust; and Allmerica Financial.

Andrew Hayek

Chief Executive Officer, OptumHealth

As chief executive officer for OptumHealth, Andrew Hayek oversees the care delivery and ambulatory care capabilities of OptumCare, as well as the distinctive and diverse care management, behavioral health, and consumer offerings of Optum.

Hayek joined Optum in 2017 through the acquisition of Surgical Care Affiliates (SCA) where he served as chairman and chief executive officer. He joined SCA as president and chief executive officer in 2008, directing its growth into one of the most successful and trusted value-based care organizations in the country. 

Prior to SCA, Hayek served as the president of a division of DaVita Healthcare Partners; president and chief operating officer of Alliance Healthcare Services; and in roles at Kohlberg Kravis Roberts & Co. and the Boston Consulting Group.

Hayek is a Henry Crown Fellow at the Aspen Institute and earned a B.A., summa cum laude, from Yale University.

Richard Mattera

Executive Vice President, Chief Legal Officer

As executive vice president and chief legal officer for Optum, Richard Mattera is responsible for all legal, regulatory and compliance activities.

Mattera joined UnitedHealth Group’s corporate legal team in 2012 with responsibility for the Securities, Transactions and International legal group. This group oversees the securities law compliance, capital markets, investments, real estate, M&A, joint ventures, key strategic transactions and international legal functions enterprise-wide. Mattera started at UnitedHealth Group in 2011 with Optum, providing legal support for M&A, joint ventures and key strategic transactions. 

Prior to joining UnitedHealth Group, Mattera was a partner at the international law firm of Hogan Lovells and represented publicly and privately held companies in a variety of matters, including in the areas of M&A, joint ventures, securities, corporate finance and corporate governance. 

Mattera earned his J.D. from The Ohio State University, Moritz College of Law and received his B.A. in political science from Pennsylvania State University, with high distinction. He currently serves on the Board of Directors of Twin Cities Habitat for Humanity.

Dirk McMahon

President, Chief Operating Officer

Dirk McMahon is responsible for Optum-wide enterprise performance and oversees OptumInsight, Optum Technology, operations, Optum administration and business and corporate strategy.

McMahon has served in a number of key leadership roles spanning the enterprise over the past 14 years, including executive vice president, UnitedHealth Group Enterprise Operations and chief executive officer of OptumRx.

Prior to Optum, McMahon held various management positions in information technology, operations and finance at UnitedHealthcare, including chief executive officer, UnitedHealthcare Benefit Operations. Earlier in his career, McMahon was head of airport operations worldwide for Northwest Airlines.

McMahon has an M.B.A. from the University of Notre Dame and a B.S. in Finance from Marist College.

Erin McSweeney

Executive Vice President, Chief Human Resource Officer

With over 30 years of experience as an HR professional, McSweeney is an experienced strategic change agent with a track record of elevating organizations and cultures. Prior to joining Optum, she was Executive Vice President, global human resources for IT leader EMC Corporation (now Dell EMC), with responsibility for executive, leadership and employee development; compensation and benefits; staffing; and a global network of HR professionals advising EMC’s business leaders.

Prior to that, she led Human Resources for EMC’s product and marketing divisions, supporting nearly 15,000 employees worldwide. She also served as Chief Human Resources Officer at VCE – a joint venture of EMC, Cisco, and VMWare, and now a full business unit within EMC.

McSweeney earned a Bachelor of Science degree from the University of New Hampshire, a Master’s degree in Business from Suffolk University and a Juris Doctor from New England Law School, where she was the1995 recipient of the American Jurisprudence Award in Employment Law and Practices.

Eric Murphy

Chief Executive Officer, OptumInsight

Prior to being named chief executive officer of OptumInsight, Eric Murphy was Enterprise Growth Officer for Optum, connecting clients across the health system with the company's uniquely powerful breadth of capabilities and expertise. Murphy joined Optum in 2008 and previously led the Optum Payer Solutions business, helping health plans achieve their growth, clinical management, and operations and administration goals.

Murphy has more than 30 years of experience in outsourcing, systems integration and consulting services. Prior to joining Optum, he served as president, Business Development, Global Outsourcing Services for Computer Sciences Corporation, where he was responsible for a team with an annual new business revenue target of $7 billion across multiple industries, including health care. Before that, he was co-founder and executive vice president of Agilera, Inc., a management consulting partner at Ernst & Young LLP, and vice president of the Financial Services Insurance business unit at EDS Corporation.

Murphy holds a B.S. degree from the Brown School of Petroleum Engineering, Marietta College.

Lynn Myhran

Senior Vice President

As senior vice president at Optum, Lynn Myhran has responsibility for leading strategic and operational initiatives to help advance the organization’s key priorities. She guides the delivery of integrated communications both internally and externally, ensuring the Optum story is told with consistency and clarity. She also oversees Optum’s global real estate portfolio.

Myhran oversaw human capital at Optum from 2011 to 2016, guiding development of an innovative workforce and collaboration-based culture as the company grew from 35,000 to 120,000 employees.

Myhran joined UnitedHealth Group in August 2002, and prior to joining Optum progressed through a series of human capital leadership roles encompassing technology, corporate and international business. Her more than 25 years of professional experience also includes leadership positions at Arthur Andersen and ITT Consumer Financial Corporation. She is a former board member of the Jacob Wetterling Foundation in St. Paul, Minn.

Myhran holds a Bachelors of Arts from the College of St. Benedict in St. Joseph, Minn.

John Prince

Chief Executive Officer, OptumRx

John Prince serves as chief executive officer of OptumRx, an industry-leading provider of pharmacy care services.

Previously, Prince served as executive vice president and chief operating officer of Optum. He has held numerous roles with UnitedHealth Group since 2005, including executive vice president and chief financial officer of Optum; the first chief operating officer of OptumHealth; and led the formation of OptumHealth Financial Services as its chief executive officer.

Prior to joining UnitedHealth Group, Prince served as senior vice president and head of health care business development and strategy at JPMorgan Chase and was a partner in Arthur Andersen’s health care strategy and operations practice.

Prince holds an undergraduate degree in economics and mathematics from Northwestern University, as well as an M.B.A from Northwestern’s Kellogg School of Management. He is also actively involved with the Minneapolis Institute of Arts.

Tami Reller

Executive Vice President

Tami Reller serves as executive vice president and leads the Optum Growth organization, which includes the Growth Office, Brand and Marketing, Optum International and OptumLabs.

Previously, Reller served as chief financial officer for Optum, a role she held following successful leadership of the company’s strategic brand and marketing initiatives.

Reller joined Optum in 2014 following an accomplished, 13-year career at Microsoft that included numerous executive leadership roles across Finance, Marketing and Product. Her time at Microsoft included five years as a corporate vice president for the Windows division, when she held dual roles of chief financial officer and chief marketing officer for Windows. She subsequently served as divisional co-leader for the Windows and Surface product businesses in addition to her Finance and Marketing accountabilities. Following this role, she consolidated all Marketing at Microsoft into one organization and provided leadership for the function.

Prior to Microsoft, Reller served as chief financial officer for Great Plains Software, a role she held through the company’s acquisition by Microsoft in 2001. She has an M.B.A. from Saint Mary’s College of California and a B.A. from Minnesota State University, Moorhead.

John Santelli

Chief Information Officer

John Santelli is chief information officer at Optum, where he leads the advancement of commercial Information Technology Outsourcing (ITO), business processing, software and cloud services. He also leads Optum technology strategy, planning, coordination and integration with the UnitedHealth Group technology agenda, with a focus on providing innovative solutions across the enterprise. Santelli has played a pivotal role in technology growth and development at UnitedHealth Group. He held the position of chief information officer for Uniprise Technologies from 2004-2006, and chief technology officer for UnitedHealth Group in UnitedHealth Technologies from 2002-2004. He led enterprise architecture and strategic system planning for UnitedHealth Group, established enterprise technology direction with UnitedHealth Group businesses and developed much of the corporate technology architecture.

Santelli joined UnitedHealth Group in 1986 and has extensive experience in software engineering and application development. He has a strong background in the development of high-volume transaction processing systems and medical claim-related systems. He holds a Master’s degree in software engineering from Union College, Schenectady, N.Y. He received his undergraduate degree in computer science from State University of New York, Brockport.

Lynne Stockstad

Executive Vice President, Chief Marketing Officer

Lynne Stockstad serves as chief marketing officer for Optum. She is responsible for the company's strategic brand and marketing initiatives and chairs an enterprise-wide product leadership team that leads Optum’s integrated product strategy and delivery.

Stockstad joined Optum in December 2014 as senior vice president of Product and Consumer Marketing.  In that role, she led a team of marketers supporting a broad spectrum of health services products – ranging from technology, managed services and consulting – used by health plans, employers, providers, life sciences organizations, government and consumers.

Prior to joining Optum, Stockstad served for 12 years in global leadership roles at Microsoft, spanning product management, product marketing, business development, enterprise marketing and public sector marketing.  Her earlier experience includes leadership roles at Great Plains Software, where she spent 15 years helping to build the organization from a small startup through a successful IPO and, later, acquisition by Microsoft.

Stockstad has a B.S. in Marketing from Minnesota State University, Moorhead. 

Michael Weissel

Group Executive Vice President

Mike Weissel joined Optum in 2013 as executive vice president and CEO of the Consumer Solutions Group.  The Consumer Solutions Group provides solutions to help sponsors improve population health and consumers to take better control of their health care needs. 

Prior to joining Optum, Weissel was with leading international management consulting firm Oliver Wyman for 17 years. He founded Oliver Wyman’s Health & Life Sciences practice in 2007, and served as managing partner and global leader for that practice until 2013. He also held a variety of roles for Marsh & McLennan, Oliver Wyman’s parent company, related to leading cross-company collaboration focused on the health care space. Weissel has provided strategic leadership on a wide range of issues for health care system participants, with a specific emphasis on payers, health services and enablement companies. He has deep industry experience in health care reform, exchange and distribution strategies, value-based healthcare, customer and account management activities and organizational transformation. Prior to Oliver Wyman, Weissel was a Certified Public Accountant and associate partner at Price Waterhouse.

Weissel has been widely published on a variety of health care-related topics in leading journals, including Harvard Business Review. He holds an MBA from Duke University and a BA from the University of Massachusetts.

Tim Wicks

Executive Vice President, Chief Financial Officer

Over the past 13 years, Tim Wicks has held a broad range of executive leadership positions across UnitedHealth Group, including president and chief executive officer of OptumRx, and various roles in operations, product management, business development and strategic relationships at both UnitedHealthcare and Optum.

Previously, Wicks was chief financial officer, and president and chief operating officer, of a Fortune 500 publicly-traded transportation and logistics service provider. He has served on the board of two publicly traded companies as a financial expert and has held executive positions at Dell, Inc., Northwest Airlines and Bain & Company. In addition, Tim co-founded a registered investment advisory firm that developed quantitative investment strategies for institutional clients.

Wicks holds a B.A. in economics from the University of Chicago and an M.B.A. from Harvard University’s Graduate School of Business.

Travis Winkey

Executive Vice President, Corporate Development

Travis Winkey serves as executive vice president, Corporate Development for Optum. He leads major strategic growth initiatives across the company, including acquisitions, investments, partnership opportunities and global business development priorities.

Winkey brings more than 25 years of experience in investment banking, venture capital and mergers and acquisitions to his role. Prior to joining Optum in 2009, he was the founder and general partner of BlueStream Ventures, where he helped build a number of software and technology infrastructure companies. Before that, he served as the managing director and head of mergers and acquisitions at Dain Rauscher Wessels, which became part of Royal Bank of Canada.

Winkey has a Master’s of Business Administration from The University of Chicago Booth School of Business and a Bachelor of Arts degree from Wartburg College.

Norman Wright

Chief of Operations

As chief of operations at Optum, Norman Wright is responsible for leading the Optum Operations teams, Optum Global Solutions and the Optum Relationship Office.  

Previously, Wright was responsible for delivering a best-in-class experience to Optum clients across all product and service categories. He joined Optum in 2013 after a career in the financial services and retail industries. Prior to Optum, Wright was the Managing Director, Client Experience for Citigroup’s Consumer Operations in North America.    

Wright was also a partner with the consulting firm Accenture, where he led a practice in call center transformation for the financial services and retail industries. Before Accenture, he led customer care at Home Shopping Network. Wright also managed call center operations and technology at Fidelity Investments, GE Capital and Chase Manhattan Bank. 

Wright has a B.A. in political science from Swarthmore College. He currently serves on the United Health Foundation Board and Charitable Giving Committee.