Parking at the south side of
the building off of Mason Street.


Northern Oak

Northern Oak Wealth Management, Inc. is one of the Midwest’s premier wealth management companies. We pride ourselves on our level of service and communication with our clients. Our professionals are always available for consultation.

New clients can call
to start a relationship with us.
Mark Zellmer

Mark Zellmer graduated from Marquette University with a Bachelor of Business Administration degree in 1981. He returned to the university and earned his Master of Business Administration degree in 1986.

He began his investment career with a Milwaukee-based brokerage firm in 1982 and eventually formed his own investment management company. He sold his firm to Blunt Ellis & Loewi in 1984. He became assistant vice president at Blunt Ellis & Loewi and later vice president as it evolved into Capital Investment Services of America, Inc. Mr. Zellmer joined Haker Investment Management in 1989 as vice president and became the firm’s president in April 2000.

Mr. Zellmer is now the majority shareholder of Northern Oak Wealth Management. He is active in the business community and has interests in several private companies. In addition, he serves as an adjunct instructor of finance at Marquette University, teaching portfolio management and entrepreneurial finance at the undergraduate and graduate levels.


David Becker

David Becker graduated from the University of Wisconsin-Madison with a Bachelor of Business Administration degree in accounting in 1991. He returned to the university and earned a Master of Science degree in finance in 1996, while participating in the school’s Applied Security Analysis program.

From 1991-94, Mr. Becker worked as a staff auditor for Deloitte in its Minneapolis and Milwaukee offices. He then joined Campbell Newman Asset Management, Inc. as an associate director of research from 1996-2001. During his time there, he earned the Chartered Financial Analyst designation.

Mr. Becker joined Northern Oak Wealth Management in 2001. He is president of the firm and a shareholder. He is also a former president of the CFA Society of Milwaukee.



David Szatkowski
Senior Vice President and Senior Portfolio Manager

David Szatkowski has 41 years of experience in portfolio management and investment analysis. He graduated from the University of Wisconsin-Madison in 1971 with a Bachelor of Business Administration degree in finance, investment and banking.

Mr. Szatkowski is a Chartered Financial Analyst and a Chartered Investment Counselor. He began his career in 1971 at R.F. Newman Inc. as a research analyst and assistant portfolio manager. He stayed with the firm through its merger with Campbell Newman Asset Management, Inc.. During his 30 years with Campbell Newman, he held titles of senior portfolio manager, chief compliance officer and managing director.

Mr. Szatkowski joined Northern Oak Wealth Management in March 2008 as senior vice president and senior portfolio manager. He also assists with the firm’s SEC and compliance functions, and he holds stock in the company.

Matthew Bappert
Portfolio Manager

Matthew Bappert received a Bachelor of Science degree with a focus in public financial management from Indiana University in 2011.

He began his career the same year at Wintrust Financial Corporation as a credit analyst, with the principal responsibility of underwriting commercial industrial and commercial real estate credit.

In 2013, Mr. Bappert joined FactSet, a provider of portfolio management and analytics software. He consulted institutional portfolio managers, research analysts and wealth management clients.

Lynn Vorbeck
Vice President and Operations

Lynn Vorbeck received her Bachelor of Arts degree from Milwaukee’s Mount Mary College in 1976. She then earned an MBA with a concentration in finance and accounting from Keller Graduate School of Management in 1989.

Ms. Vorbeck has been with Northern Oak for more than 20 years. She is the vice president and oversees corporate operations. Her responsibilities include portfolio accounting and maintenance, billing and receivables, client and composite performance, electronic trade processing, new accounts, compliance, and government reporting. She is also a shareholder.

Lindsey Riese
Operations Administrator

Lindsey Riese earned a Bachelor of Business Administration degree in finance from the University of Wisconsin-Milwaukee in 2008. During her last year of school, she worked as an intern for Stark Investments in the operations department.

Ms. Riese worked as a reconciliation analyst at Stark Investments in St. Francis, Wisconsin, from 2008-12 before joining Northern Oak.

Kerri Schanowski
Client Relations Manager

Kerri Schanowski works closely with Northern Oak’s clients and portfolio managers to ensure the firm fulfills all client requests. She makes customer service her priority.

Ms. Schanowski has 19 years of experience in the insurance and investment advisor industries. Her expertise lies in operations service and insurance, training, call center management, and client services.

Deanne Pick
Executive Assistant

Deanne Pick works closely with our personnel as our executive assistant. She has an extensive background in administrative work. Customer service has always been a top priority for Ms. Pick, and she enjoys being a part of the Northern Oak Wealth Management team.