Our Team

Ryan P. Graham
Managing Partner and Founder

Ryan grew up in a medical family as the son of an orthopedic surgeon. For the last 15 years, he has identified and implemented cost reduction and growth opportunities to drive meaningful improvement to the bottom line. From leading outside diligence efforts on the buy-side for private equity firms to implementing sourcing and procurement initiatives for multi-unit businesses, Ryan has deep operational expertise with a track record of growing EBITDA through revenue and margin improvement.

Ryan earned his MBA from the Kellogg Graduate School of Management at Northwestern, and his BS in Business Administration from the University of Southern California. He is still very passionate about California sports including the Angels, and enjoys international travel which he hopes to pursue more with his family in the future.

Daniel J. Hosler
Managing Partner and Founder

Dan also grew up in a healthcare family with a mom who is a nurse anesthetist, and a dad who both built an ASC and ran a successful gastroenterology practice. Dan has both operational experience, having started three companies before business school, as well as deep deal experience, having spent 15+ years in private equity. Most recently he led M&A for an eye care rollup where he closed 10 deals in under two years. He knows the universe of buyers, what private equity looks for in a deal, and how to make operational improvements to increase the value of a medical asset.

Dan earned his MBA from the Kellogg Graduate School of Management at Northwestern, and his BA in Biochemistry from Rice University. When he’s not working with doctors, he enjoys grilling outdoors, searching for rare bourbons, and spending time outside with his family.

Brian A. Hamilton
Managing Director

Brian has deep experience investing in early-stage and growth-stage companies, providing strategic leadership and direction in both finance and growth opportunities. Brian began his career in the front office of a minor league sports team, and after that, worked at a boutique investment bank and a single family office. Since then, Brian has held various corporate development roles at private equity-backed companies and most recently assisted in a successful secondary buyout of a PPM company. 

Brian holds certificates from Harvard Business School’s GMP program and the Venture Capital Institute at Emory University. He received his MBA from Grand Valley State and his BA from Calvin University. Brian enjoys playing and watching sports, including his favorite sports team, the Chicago Bears. Brian also enjoys traveling with his family.

Sara Tumen Weinberg

Sara focuses on marketing and corporate communications initiatives across DuneGlass Capital and its portfolio companies. Prior to joining DuneGlass, Sara worked at a $1b Am Law 50 firm where she managed digital marketing and public relations strategies across 15 offices around the globe. Before that, Sara directed marketing & comms for a $6b middle market private equity firm. Sara began her career in Washington, D.C. as a Schedule C Appointee in former President Barack Obama’s administration, focusing on intergovernmental affairs at the Department of the Interior. Sara has deep experience in building and executing omnichannel communications programs, including digital marketing, public relations, and investor relations strategies.

Sara earned her BA from the University of Michigan. In her free time, she enjoys reading mystery novels, testing new recipes with her husband, and playing ball with her dog, Gus.

Hyung Kim, MD, MBA
Operating Partner

Dr. Hyung Kim is Board Certified in Internal Medicine and an accomplished physician executive. His career includes  the healthcare leadership at renowned consultancy McKinsey & Co, the senior leadership team at Ascension Health, as CEO of SIU HealthCare; he was most recently he was President of Mercy Health Saint Mary’s, an $800 million health system within Trinity Health.

He also serves on the Boards of the Grand Rapids Symphony and the Great Lakes Chapter of the American College of Healthcare Executives. His BA and MD are from Johns Hopkins, and his residency and his MBA were at the University of Michigan. He is a Fellow of the American College of Physicians and the American College of Healthcare Executives.

Dr. Kim is a devoted family man who enjoys marathon training, practicing piano and baking bagels.