Kate Mathieu advises public and private companies on a broad range of domestic and international tax matters, primarily concentrating in corporate mergers, acquisitions and dispositions, spin-offs, and partnership transactions. Ms. Mathieu also has experience in the tax aspects of bankruptcy restructurings, initial public offerings, tax-equity financings and internal integration and restructuring transactions.

Some of her significant representations include:

  • General Mills, Inc. as special tax counsel in its $8 billion acquisition of Blue Buffalo Pet Products, Inc.
  • Eli Lilly and Company as special tax counsel in a tax-efficient separation of its global animal health business into a new public company called Elanco Animal Health Incorporated, which has a market value of $11.2 billion. The separation was accomplished through a series of transactions, including a carve-out IPO by Elanco and a subsequent tax-free split-off of Eli Lilly’s remaining interest in Elanco
  • Liberty Mutual Insurance Group in the:
    • $3.3 billion sale of Liberty Life Assurance Company of Boston to Lincoln National Corporation
    • cross-border acquisition of four businesses from AmTrust Financial
  • The Advisory Board Company in its $2.6 billion sale of its health care business to OptumInsight, Inc. and its education business to affiliates of Vista Equity Partners LLC in response to Elliott Management Corporation’s activist campaign
  • Duke Energy Corporation in two transactions totaling $2.4 billion: the $1.2 billion sale of its Brazilian business to China Three Gorges Corporation and the $1.2 billion sale of its international businesses in Peru, Chile, Ecuador, Guatemala, El Salvador and Argentina to I Squared Capital Advisors, LLC. This transaction was named Latin America Power M&A Deal of the Year by Power Finance & Risk and Cross-Border M&A Deal of the Year by LatinFinance
  • Citrix Systems, Inc. in the merger of its GoTo business with LogMeIn, Inc. through a Reverse Morris Trust transaction valued at $1.8 billion
  • Peraton Corp., a portfolio company of Veritas Capital, in its:
    • acquisitions of Strategic Resources International and Solers, Inc.
    • $690 million acquisition of the government IT services business of Harris Corporation
  • Excelitas Technologies Holding Corp., a portfolio company of Veritas Capital, in connection with a dual-track process that included a proposed initial public offering of common stock and culminated in an acquisition by funds sponsored by AEA Investors

Ms. Mathieu is an adjunct professor at George Washington University Law School, where she teaches a class on corporate income tax.



  • J.D., The University of Chicago Law School, 2014
  • B.A., The University of Texas, 2011


  • Texas
  • District of Columbia