Founder and Managing Partner of Serengeti Asset Management, a value-driven investment firm that focuses on niche credit opportunities defined by their small size and complexity. It invests in performing debt and high-yielding opportunities. Serengeti provides institutions and private company executives with sophisticated solutions to funding challenges. Investments can include steady debt, liquidations, litigation finance, stressed and distressed corporate and sovereign debt, off-the-run structured credit, reinsurance, and financing platforms.

Prior to launching Serengeti in 2007, Mr. LaNasa was a partner at Goldman Sachs where he headed the Multi-Strategy Investing Business (“MSI”) in the Special Situations Group. MSI was a multi-billion dollar proprietary investment business focused on similar opportunities.

Mr. LaNasa graduated from Harvard Law School (J.D. magna cum laude) and Georgetown University’s School of Foreign Service (B.S.F.S. summa cum laude). He was an attorney at Wachtell Lipton Rosen & Katz in their creditors’ rights and corporate departments and clerked for Judge Adrian G. Duplantier of the U.S. District Court for Eastern District of Louisiana (New Orleans).

He serves on Harvard Law School’s Advisory Board and now serves on the Advisory Board for Georgetown University’s School of Foreign Service and previously served on Georgetown’s Board of Regents.


Leslie D. Biddle is a partner and the president of Serengeti where she heads the firm’s research efforts and risk committee. Prior to joining Serengeti, Ms. Biddle was the Global Head of Commodity Sales at Goldman Sachs and member of the senior commodities management team contributing to the growth of the business from approximately $450 million to more than $3 billion. She was a member of Goldman’s firmwide Finance Committee, Business Practices Committee, New Activity Committee, Structured Investment Products Committee and European Audit and Compliance Committee. She was named managing director in 2004 and partner in 2006. While at Goldman, Ms. Biddle was the architect of many structured transactions in the private equity and energy sectors including the monetization of Allegheny DWR Contract, the financing for the Calpine Construction Finance Facility, the Texas Genco acquisition, Northern Tier Energy and the TXU leveraged buyout, among others.

Prior to joining Goldman Sachs, Ms. Biddle was a Vice President at the AES Corporation focusing on project finance and power plant development and acquisitions. She also served as a vice president at the Overseas Investment Corporation, providing political risk insurance and financing to U.S. companies expanding overseas.

She holds an A.B. from Colby College where she previously served as Vice Chair of the Board of Trustees. She is a member of the Board of Directors of the Empire State Realty Trust (NYSE), CenterPoint Energy (NYSE) and the Advisory Board of NatureVest, the impact investing arm of The Nature Conservancy. Ms. Biddle was twice named to the Hedge Fund Journal’s Top 50 Women in Hedge Funds, is a member of the Council on Foreign Relations and the Global Advisory Board of The Hawthorn Club for executive woman in energy. She lives in New York, New York with her husband, George, and their three children.


Jay Eisbruck is the Head of Structured Credit and Senior Managing Director at Serengeti Asset Management. At Serengeti, Mr. Eisbruck manages the structured credit portfolio and covers other structured finance related debt and equity positions.

Prior to joining Serengeti Asset Management in 2008, he was a team managing director in the asset-backed finance group at Moody’s Investors Service, where he worked from 1991 to 2007. While at Moody’s, Jay co-managed the group responsible for rating all non-residential mortgage asset-backed securities including autos, credit cards, equipment leasing, intellectual property and whole business securitization.

He received his MBA in finance in 1994 and his B.S. in economics in 1991 from the Leonard N. Stern School of Business at New York University, where he was a Racoosin scholar.

Raza Mujtaba is the Head of Public Investments and Senior Managing Director at Serengeti Asset Management.

Prior to joining Serengeti Asset Management in 2018, he was a Partner and Portfolio Manager of Global Distressed Debt, High Yield and Special Situations Equities strategies at Tricadia Capital Management. Raza was a member of the corporate credit investment committee and also managed a short credit portfolio for Tricadia’s short-biased convexity fund. Before joining Tricadia Capital, Raza worked from 2004 to 2008 as a Senior Analyst at Anchorage Capital, whose two co-founders he had previously worked with at Goldman Sachs. There, he focused on credit and equity strategies. Raza started his career in 2000 at Goldman Sachs as an analyst in the Asset Management division (GSAM), before joining the Distressed Debt group in the Fixed Income division. In the Distressed Debt group, he worked closely with Jody.

Mr. Mujtaba holds a BA degree in Economics from Amherst College where he played varsity squash at NCAA Division 1 level.


Robert Sumberac is the Chief Operating Officer, Chief Financial Officer and Senior Managing Director at Serengeti Asset Management.

Prior to joining Serengeti, Mr. Sumberac was Chief Financial Officer and Managing Director at D.B. Zwirn & Co, a global multi-strategy alternative investment firm. He joined D.B. Zwirn just prior to the in-house discovery of reporting and accounting issues and was instrumental in the forensic review and correction of these issues and the restructuring of the firm’s procedures, processes and back office organization. Prior to that, he was Treasurer and Corporate Controller at Cantor Fitzgerald. Previously, Mr. Sumberac was a Vice President at Goldman Sachs in the Firmwide Funding group where he focused on accounting and treasury issues.

Mr. Sumberac received his B.B.A. in Accounting from the University of Notre Dame.

A.J. joined Serengeti in June 2018. Prior to joining Serengeti, A.J. was an attorney in the litigation department at Wachtell, Lipton, Rosen & Katz, where his practice focused on the litigation and negotiated resolution of disputes relating to distressed debt, corporate governance, and the financial services industry. Before his time at Wachtell Lipton, A.J. was a clerk for Judge John T. Noonan, Jr. of the U.S. Court of Appeals for the Ninth Circuit and an associate at Cravath, Swaine & Moore, LLP.

A.J. graduated cum laude from New York University School of Law. He also holds an M.Phil. in History from Cambridge University and an A.B. in History from Princeton University.