Baltimore Orioles

Owner: Peter Angelos

Net Worth: $1.2 billion (2008)

Source of wealth: Lawyer

2010 Forbes Franchise Valuation: $376 million

After graduating from the University of Baltimore School of Law Angelos worked as a criminal defense lawyer. In 1961 he started his own practice and in the early 1980’s he represented a number of plaintiffs in asbestos litigation and won. He reportedly made over $100 million at this time. He also won class-action law suits against Philip Morris (cigarettes) and the drug maker Wyerth for the diet pill fen-phen.

In 1993, he led a group of investors that purchased the Baltimore Orioles for $173 million from Eli Jacobs.

Boston Red Sox

Owner: John Henry, Tom Werner and Larry Lucchino

Net Worth (Henry): $1.1 billion (2008)

Source of wealth: Investor – futures and foreign exchange

2010 Forbes Franchise Valuation: $870 million

He attended Victor Valley College and the University of California at Riverside, Irvine and Los Angeles, but he did not graduate because he performed on the road in two rock and roll bands.  In 1981 he founded John W. Henry & Company (JWH) in Irvine, California and began marketing his money management to the largest commodity brokerage firms in America. Henry developed a mechanical trend following method for managing a futures trading account that proved to be very successful.

Henry owned a small interest in the New York Yankees in 1991 and then became the sole owner of the Florida Marlins in 1999 for $158 million. He sold the Marlins in 2002, and simultaneously lead a purchase of the Boston Red Sox for $380 million.

New York Yankees

Owner: George Steinbrenner

Net Worth: $1.3 billion (2008)

Source of wealth: Shipping and entertainment investing

2010 Forbes Franchise Valuation: $1.6 billion

While working on his masters degree at the Ohio State University, he served as a graduate assistant to coach Woody Hayes. He then went on to serve as assistant football coaches at Northwestern University and Purdue University. In 1957, he joined his grandfather’s company – Kinsman Marine Transit Company. He revitalized the company and eventually purchased the company from his family.  He later became part of a group that purchased the American Shipbuilding Company which eventually had gross revenues of more than $100 million annually.

Steinbrenner led a group of investors to purchase the Yankees from CBS for $10 million. The deal also included two parking garages which CBS bought back for $1.2 million. The net cost of the Yankees was $8.8 million.

The Yankees are officially owned under Yankee Global Enterprises LLC with sons Hank Steinbrenner and Hal Steinbrenner in charge of the team.

Tampa Bay Rays

Owner: Stuart Sternberg

Net Worth: unknown

Source of wealth: Investing

2010 Forbes Franchise Valuation: $316 million

While attending St. Johns University, Sternberg traded equity options at the American Stock Exchange. He later was hired by the investment group Spear, Leeds & Kellogg and eventually became partner in the firm before moving to Goldman Sachs.

He purchased a 48% share in the Tampa Bay Devil Rays (now Rays) in May 2004, and he eventually took majority ownership for a total of $200 million.

Toronto Blue Jays

Owner: Rogers Communications

Net Worth: $15.65 billion market cap

Source of wealth: Communications, wireless technology and cable television

2010 Forbes Franchise Valuation: $326 million

Rogers Communications Inc. acquired the Blue Jays in 2000 for $137 million from Interbrew S.A. and The Canadian Imperial Bank of Commerce. Rogers eventually acquired their stadium, Skydome.