Byrne, Jefferies, Stoneman Named Among Legal 500 Elite

October 29, 2025 Firm News

Armstrong Teasdale Partners Jennifer R. Byrne, Michael S. Jefferies and Mark L. Stoneman have been recognized among the Legal 500’s inaugural Elite City Focus – Missouri - Corporate and M&A series, which highlights exceptional, city-based legal leaders who are driving innovation and growth in their practice areas.

Legal 500’s US Elite emphasizes lawyers who are handling work at the top of the legal market in their respective cities. Lawyers are selected based on interviews with top practitioners, referee and peer feedback, and evidence of key matters worked on by the ranked attorneys during the past year.

Byrne concentrates her law practice in mergers and acquisitions, securities and corporate finance, general corporate issues, corporate governance emerging companies. She has extensive experience representing domestic and international companies from numerous industries. As outside corporate counsel to businesses, Byrne provides counsel on day-to-day transactions as well as high-stakes disputes and transformative relationships.

Jefferies works with clients across multiple industries on matters related to business operations and growth. His practice is primarily focused on mergers and acquisitions and other corporate development transactions. His transaction experience includes working with private and public company clients across the U.S. and internationally in numerous and varied industries. During his career, Jefferies has served as lead counsel in M&A transactions with total deal values in excess of $2.0 billion.

Stoneman facilitates the structuring, financing and completion of acquisitions, mergers, divestitures, joint ventures and partnerships. His background in accounting and finance helps him to ensure that the agreements related to these transactions are consistent with his client’s goals and expectations with respect to financial matters, which can be of critical importance in transactions of this nature.

The complete listings can be found at legal500.com.

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