Question: Which Ohio-based regional bank holding company did Jerry Grundhofer leave Bank of America for?

Context paragraphs:
Star Banc Corporation: Star Banc Corporation was a Cincinnati, Ohio-based regional bank holding company that became Firstar in 1998 and eventually became U.S. Bancorp in 2001.  The company can trace it origins back to 1863 when it was first founded as the First National Bank of Cincinnati.

Regional bank: A regional bank is a depository institution, i.e. a bank, savings and loan, or credit union, which is larger than a community bank, which operates below the state level, but smaller than a money center bank, which operates either nationally or internationally.  A regional bank is one that operates in one region of a country, such as a state or within a group of states.  The definition of what constitutes a regional bank is not precise.  They generally provide, with some limitations, the same services as larger banks, such as deposits; loans, leases, mortgages, and credit cards; ATM networks; securities brokerage; investment banking; insurance sales; and mutual fund and pension fund management.  The term is often used in stock trading, when referring to investing in different bank types, usually referred to as regional bank ETF's (exchange-traded funds).

Associated Banc-Corp: Associated Banc-Corp is a U.S. regional bank holding company providing retail banking, commercial banking, commercial real estate lending, private banking, specialized financial services, and insurance services.  It is headquartered in Green Bay, Wisconsin.  It is the largest bank (by asset size) headquartered in Wisconsin.  The bank's main focus is middle-market commercial banking in Wisconsin, Illinois, Minnesota, and the upper Midwest.

National City Corp.: National City Corporation was a regional bank holding company based in Cleveland, Ohio, USA, founded in 1845; it was once one of the ten largest banks in America in terms of deposits, mortgages and home equity lines of credit.  Subsidiary National City Mortgage is credited for doing the first mortgage in America.  The company operated through an extensive banking network primarily in Ohio, Illinois, Indiana, Kentucky, Michigan, Missouri, Pennsylvania, Florida, and Wisconsin, and also served customers in selected markets nationally.  Its core businesses included commercial and retail banking, mortgage financing and servicing, consumer finance, and asset management.  The bank reached out to customers primarily through mass advertising and offered comprehensive banking services online.  In its last years, the company was commonly known in the media by the abbreviated NatCity, with its investment banking arm even bearing the official name NatCity Investments.

Sterling Bancorp: Sterling Bancorp is a regional bank holding company whose principal subsidiary, Sterling National Bank, provides a full range of banking and financial services to business owners, their families, and consumers, primarily in the greater New York metropolitan and Hudson Valley regions.  Sterling National Bank had assets of nearly $12 billion at December 31, 2015.  Headquartered in Montebello, New York, Sterling Bancorp's shares are traded on the New York Stock Exchange (NYSE:STL).

Yadkin Financial: Yadkin Financial Corporation was a bank holding company and the parent of Yadkin Bank, a defunct regional bank with $7.3 billion in assets and 110 branches in North and South Carolina before the 2017 purchase by FNB Corporation of Pittsburgh.  The bank was headquartered in Elkin, North Carolina.  On July 4, 2014, Yadkin Financial and VantageSouth Bancshares Inc. completed a merger which resulted in the largest community bank based in North Carolina, and the fourth-largest bank headquartered in the state, with $4 billion in assets and $3.2 billion in deposits.  The company was headquartered in Raleigh, North Carolina with banking operations based in Statesville, North Carolina.

First Bank System: First Bank System was a Minneapolis, Minnesota-based regional bank holding company that later became U.S. Bancorp, a nationwide bank corporation in the United States.  In 1997, First Bank System acquired U.S. Bancorp and assumed its name, while maintaining its officers and its headquarters in Minneapolis.

Nicolet Bankshares: Nicolet Bankshares is a U.S. regional bank holding company based in Green Bay, Wisconsin.  They are the parent company of Nicolet National Bank, the fourth largest Wisconsin based bank.

Jerry Grundhofer: Jerry Grundhofer (born 1945) is the former CEO and Chairman of U.S. Bancorp.  He graduated from Seattle University in 1965.  In 1993, he became the president of Star Banc Corporation and held that position until 1998, when it merged with Firstar Corporation.  He had been the CEO of U.S. Bancorp since February 2001, and had been Chairman of the Board since 2002.  Jerry Grundhofer stepped down as CEO on December 12, 2006 and was replaced by his longtime lieutenant Richard K. Davis who assumed the position of CEO in addition to his current role as President.  Jerry Grundhofer was to remain as Chairman of the Board of Directors until the end of 2007 when he was scheduled to retire.  Jerry was a former Vice-President of Security Pacific Bank and Bank of America when that institution bought out Security Pacific Bank in the early 1990s.  He left Bank of America to join Star Banc Corporation in 1993.

Commercial National Financial: Commercial National Financial Corporation is a registered financial holding company under the Bank Holding Company Act of 1956 as amended.  The company wholly owns Commercial Bank & Trust of PA under the Bank Holding Company Act.  The company’s principal business is the operation of Commercial Bank & Trust of PA, which offers various commercial banking and trust services including offering deposit services, providing financial counseling, investing and extending credit.  Commercial National Financial Corporation uses CNAF as the trading symbol on the OTCQB tier of the OTC Markets.

Supporting paragraphs: Jerry Grundhofer Star Banc Corporation
Answer: Star Banc Corporation