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Mayer Brown

Work +1 713 238 3000
Fax +1 713 238 4888

William Heller

Work +1 713 238 2684
Mayer Brown

Work Department

Corporate & Securities


Bill Heller represents clients in corporate and securities law matters, with a focus on the energy industry, including oilfield services and upstream oil and gas. He has extensive experience representing public and private companies in mergers, acquisitions and dispositions of businesses and assets; offerings of equity and debt securities; SEC reporting and securities law compliance; and in advising directors, boards and special committees on corporate governance matters, including fiduciary duties.


The University of Texas School of Law, JD 1991; Rice University, BA, magna cum laude 1988, Phi Beta Kappa

United States: Finance

Capital markets: equity offerings

Within: Capital markets: equity offerings

Mayer Brown’s national practice is led out of Chicago by Edward Best and also draws upon key names in New York, Houston and Palo Alto. The team is well versed in the full spread of equity deals and routinely acts for issuers, investment banks, financial sponsors, placement agents and selling shareholders in major deals. In a significant highlight, New York’s George Baptista advised Companhia de Saneamento do Paraná on its $496m IPO. New York’s David Bakst is a high-profile figure in the team and assisted Adaptimmune Therapeutics with its $61.9m offering of American depositary Shares. New York-based John Berkery and Houston-based William Heller are also recommended. In a significant development, the firm recently hired a new capital markets team from Morrison & Foerster LLP, which included new global group co-head Anna Pinedo and Jerry Marlatt, as well as tax specialists Thomas Humphreys and Remmelt Reigersman - all join the New York office, except Reigersman who joins in Palo Alto. In November 2018, Phyllis Korff joined in New York from Skadden, Arps, Slate, Meagher & Flom.

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Capital markets: high-yield debt offerings

Within: Capital markets: high-yield debt offerings

Mayer Brown’s high-yield debt practice, which is led out of Chicago by Edward Best, has a strong emphasis on issuer representations but also has significant underwriter-side experience. Houston’s William Heller is a key contact for energy-related securities matters and recently assisted Halcón Resources with its $850m notes offering. Palo Alto-based Jennifer Carlson advised Plastipak Holdings on its $500m notes issuance. Among its manager side work, the firm acted for an underwriter on Cydsa’s $330m offering of senior notes. John Berkery and Houston’s Harry Beaudry are also noted. In 2018, the firm hired a new capital markets team from Morrison & Foerster LLP, which included new global department co-head Anna Pinedo, and Jerry Marlatt as well as tax specialists Thomas Humphreys and¬ Palo Alto-based Remmelt Reigersman. Individuals are based in New York unless otherwise stated.

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