Mark Ambrose

Managing Partner


Mark Ambrose is the Managing Partner and Founder of Flagstone Operating Partners, LLC.   Mark has a broad background spanning business operations, finance, sales strategy & go-to-market planning and corporate development, acquired over the course of more than 20 years in public and private operating companies and in investment banking.   


Most recently, Mark was Chief Operating Officer at IgnitionOne, a 300+ person digital marketing services and technology provider, where he was responsible for strategic and operational planning and oversight of global teams (US, EU, LATAM) spanning solution design, campaign & audiences services, account management, analytics and business intelligence.  His efforts at IgnitionOne were instrumental in helping to clarify the strategic direction for the future of the business and realign, simplify and streamline operations in support thereof.


Prior to IgnitionOne, Mark held senior leadership positions at Neustar (acquired by Golden Gate Capital for nearly $3B), a leading provider of real time information & analytics, internet security and infrastructure services.  While at Neustar, Mark was Vice President of Business Operations of a nearly $200M business unit, as well as Vice President of Global Sales Operations.  His leadership in the areas of performance management, financial oversight, organizational design and change management were instrumental in helping the company successfully realign in support of its efforts to become a more robust player in the information services and analytics space. 


Mark has also held executive leadership roles spanning finance, business operations and corporate development at ARPU, a venture-backed subscription management and online advertising platform, and SunRocket, a provider of voice over IP services.  Earlier in his career, he worked for a number of years at AOL and as an investment banker at Deutsche Bank Alex. Brown. 


Mark graduated from the McIntire School of Commerce at the University of Virginia.


Mark can be reached at mark@flagstoneop.com.