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Sullivan & Cromwell LLP

125 BROAD STREET, NEW YORK 10004-2498, USA
Work +1 212 558 4000
Fax +1 212 558 3588

Yvonne S. Quinn

Work +1 212 558 3736
Sullivan & Cromwell LLP

Work Department





Partner since 1984. Co-head, Antitrust Group. Antitrust litigation, merger analysis/review and counseling work as well as general commercial litigation. Clients: consumer products companies, leading commercial banks, equity funds, investment banks, insurance companies, cable television operators, television programming suppliers, newspapers, publishers, sports franchise owners, advertising sales, healthcare, pharmaceutical and chemical companies and accounting standards boards, among many others.


ABA (Antitrust Section); NYSBA (Executive Committee, Antitrust Section); New York City Bar Association (former Chair, Antitrust and Trade Regulation Committee); FBC.


University of Michigan (MA, Economics, 1977); University of Michigan Law School (JD, 1976); University of Illinois (BA, 1973).

United States: Antitrust

Civil litigation/class actions

Within: Civil litigation/class actions

Sullivan & Cromwell LLP’s lawyers are noted for their broad-ranging antitrust expertise, which spans merger matters, criminal investigations and all types of litigation. Financial services is a real sector strength, as demonstrated by the fact that a cross-office team of New York and Washington DC attorneys led by David Braff, Amanda Flug Davidoff, practice co-head Yvonne Quinn and Penny Shane is representing multiple banks, including Barclays and Goldman Sachs, in the many class actions filed against primary dealers in the US treasuries market alleging a conspiracy to manipulate prices. In Los Angeles, Robert Sacks is defending BP in an MDL alleging that several oil companies participated in a conspiracy to manipulate the price of Brent crude oil and Brent crude oil futures by providing fixed pricing information to a publisher of benchmark price assessments.

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Merger control

Within: Merger control

Sullivan & Cromwell LLP shows ‘commercial understanding’ and brings ‘real strength of experience in US merger requirements’. Operating out of offices in New York, Washington DC, Los Angeles and Palo Alto, the team handles matters in all areas of antitrust. In the merger clearance arena, Steven Holley represented Kraft in its merger agreement with Heinz, a transaction worth $55bn. He also acted for Alcatel-Lucent in its acquisition by Nokia. Yvonne Quinn assisted Bright House Networks in its pending three-way merger agreement with Charter Communications and Time Warner Cable in order to create an $80bn cable company.

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