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Earning Our Reputation Every Day
Blackthorne’s principals bring many years of investment and business operations experience, along with a commitment to supporting clients through steadfast diligence.
We take pride in personal service, so contact one of us today to learn more.
John F. Syburg
President/Founder
John is a Chartered Financial Analyst (CFA) with a strong record spanning 30 years of diverse experience advancing the success of both public and private investors.
A graduate of The University of Wisconsin-Madison with a B.B.A. in Finance in 1979, John began his investment career at The Marine Trust Company (now JP Morgan Chase) as an equity analyst and portfolio manager of high net worth personal trust accounts. Since then, he has held a variety of positions involving both individual and institutional accounts, including as a product manager for stock index futures and options with Blunt Ellis and Loewi, and as a shareholder in Cleary Gull, a Milwaukee-based investment banking and brokerage firm focused on the institutional marketplace. Spotting an opportunity to help high net worth individuals through access to alternative investments, he founded Blackthorne Partners in fall 2006.
Today, John is active among his peers and in the community, as a member of the Association for Corporate Growth; the CFA Society of Milwaukee; the advisory board of the Center for Economic Education and the Youth Enterprise Academy; and the board of North Shore Young Life. He also sits on the board of Integrated Medical Partners, a Blackthorne portfolio company.
Mark R. Zellmer
Managing Director/Founder
With nearly three decades of investing experience, Mark brings clients broad perspective from his involvement with numerous privately held companies.
He began his investment career with a Milwaukee-based brokerage firm in 1982, and eventually formed his own investment management company. He sold that firm in 1984 to Blunt Ellis & Loewi, where he later became vice president, as the firm evolved into Capital Investment Services of America, Inc. Mark joined Haker Investment Management in 1989 as vice president, and rose to president in 2000. Today, along with being a Blackthorne partner, he is the majority shareholder and president of Northern Oak Capital Management Inc., a registered investment advisory firm that specializes in asset allocation models for high-net-worth individuals and foundations.
A graduate of Marquette University with a B.S. in Business Administration in 1981 and a M.B.A. in 1986, he also serves as an adjunct instructor of finance at the university, teaching Entrepreneurial Finance at both the undergraduate and graduate levels.
Steve Balistreri
Managing Director
Coming from a family of longtime business entrepreneurs, Steve has a long record of operational, managerial and turnaround success.
As president/CEO of Sun Cleaning Systems, he grew the company from $100,000 to $10,000,000 in sales, added over 600 employees and increased its economic value six-fold. Steve also spent several years at Marsden Holdings LLC, a privately held security and facility services company based in St. Paul, MN, as executive vice president of finance and national accounts; and, most recently, as president of Legacy Advisors LLC, a business turnaround consulting firm. As Founding Director of Spring Bank of Brookfield, WI, a startup that opened in September 2008, his team raised $12.5 million in initial capital; the bank’s assets have since reached over $100 million. He remains active in the community, including serving as president of the boards of directors of the University Club of Milwaukee, the Metropolitan Milwaukee Association of Commerce and the MMAC's Council of Small Business Executives.
Steve holds a bachelor's degree from Marquette University and a master's degree in finance from the Kogod School of Business at the American University in Washington, D.C. |
