Mr. Koester is Co-Founder and Managing Partner of 5C Investment Partners. Based in New York City, 5C is a private credit investing firm that commenced operations in 2024 with over $1.4 billion of long-term capital for investment. With an initial focus on direct lending, 5C is growing quickly, scaling its platform and private credit investment activities. 5C takes a long-term approach to working with our partners, including with our announced partnerships with Michael Dell’s family office (Dell Family Office), Liberty Mutual Investments, among other leading investors. Mr. Koester founded 5C with his long-time colleague, Tom Connolly, former Partner and Global Head of Private Credit in the Merchant Banking Division at Goldman Sachs.

Prior to founding 5C, Mr. Koester was a Partner and the Co-President of Alternatives in the Asset Management business of Goldman Sachs, where he oversaw the firm's direct Private Credit, Private Equity, Growth Equity, Infrastructure, Real Estate and Sustainability investing strategies, which collectively had over $200 billion of assets under management. During his 25 years at Goldman Sachs, Mr. Koester held numerous other senior leadership roles, including Co-Founder and Co-Head of Alternatives Capital Markets and Strategy, which oversaw the distribution of alternative investment products firmwide, and Chief Commercial Officer, Co-Chief Operating Officer, and Chief Financial Officer of the Merchant Banking Division, and served on the Merchant Banking Division Investment Committee since 2006. Mr. Koester was an investment professional in the Merchant Banking Division from 2000 to 2006.

Mr. Koester received a B.A. in Economics from Colby College, where he is Vice Chair of the Board of Trustees, and an MBA from the Tuck School of Business at Dartmouth College, where he is a member of the Board of Advisors. Mr. Koester lives in New York with his wife and four children.