Buchanan, Ingersoll & Rooney
|Buchanan, Ingersoll & Rooney P.C.|
|Headquarters||One Oxford Centre
|No. of offices||15|
|No. of attorneys||approximately 450|
|Major practice areas||Lobbying, general practice|
|Key people||John Barbour, CEO|
|Date founded||1850 in Pittsburgh|
|Company type||Professional corporation except in California, where it is organized as an LLP|
The firm was originally founded in 1850 by Congressman Moses Hampton and his son, John. When Moses Hampton became chief judge of Allegheny County, William C. Moreland was brought in as an additional partner in 1868 and the firm was renamed Hampton & Moreland. The firm continued to grow and went through several name changes before incorporating in 1980. The firm shortened its name to Buchanan Ingersoll P.C. in 1983, and acquired two other firms during the 2000s: Burns, Doane, Swecker & Mathis in 2005, and Klett Rooney Lieber & Schorling PC in 2006, leaving the firm with its current name, Buchanan Ingersoll & Rooney.
Practice areas 
Buchanan, Ingersoll & Rooney has law practices in corporate, energy, Marcellus Shale, financial services, health care, intellectual property, labor and employment, immigration, bankruptcy and creditors' rights, tax, real estate, and litigation. The firm also has the largest state-government lobbying practice in Pennsylvania and one of the top 20 federal lobbying practices nationwide.
Notable lawyers and alumni 
- John Dalzell, former U.S. Representative from Pennsylvania
- Barry Slotnick, New York City defense attorney
- David W. Marston, former United States Attorney who was ousted by President Jimmy Carter, spent a number of years working at Buchanan Ingersoll before moving to Reed Smith and later Gibbons P.C.
- Ralph J. Cappy, former Chief Justice of the Supreme Court of Pennsylvania
- Art Rooney II, President of the Pittsburgh Steelers.
- David W. Sweet, former member of the Pennsylvania House of Representatives.
- San Diego, California
- Washington, DC
- Wilmington, Delaware
- Aventura, Florida
- Miami, Florida
- Tampa, Florida
- Newark, New Jersey
- Princeton, New Jersey
- Buffalo, New York
- New York, New York
- Charlotte, North Carolina
- Harrisburg, Pennsylvania
- Philadelphia, Pennsylvania
- Alexandria, Virginia