The pair plan to form a new firm called BlueSpruce Investments, which already has a one-page website. What follows is an email recently sent by Hurd to friends and colleagues, and obtained by Fortune:

I want to take this moment to let you know that Eddie Magnus and I will be leaving MDP to start our own investment firm.  After a combined 26 years in private equity at MDP, we have decided to pursue our passion of starting our own investment firm focused on public, marketable securities.  While we’re sad to be moving on and to be leaving behind such a great firm and so many wonderful friends and colleagues, we are excited to begin this new challenge.

Our new firm will be called BlueSpruce Investments, LP and will employ a private equity approach to public market investing.  We aim to combine primary due diligence and a focus on long-term returns to construct a concentrated portfolio that only includes our “best ideas”.  Additionally, we will have the flexibility to invest across multiple asset classes, including mispriced yield-oriented securities that can be episodically purchased on a favorable risk/return basis or be patient and hold cash if those opportunities are unavailable.

BlueSpruce Investments has the backing and the support of some of the most prominent and sophisticated families and investors in the United States, and we anticipate calling down capital late in the 2nd quarter after we have completed our SEC registration process.

Madison Dearborn also sent a letter out to its limited partners, wishing the departing duo well and announcing that managing director Vahe Dombalagian would lead financial services going forward. Most recently, he led the firm’s investment in payment processing company EVO Payments.

A Madison Dearborn spokesman declined to comment. News of the departures was first reported by Becky Yerak.

Madison Dearborn currently is investing out of a $4.1 billion fund raised in 2007.

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