Aaron L. Nielson

Of Counsel Antitrust & Competition

Washington, D.C. +1 202 389 5180

Salt Lake City +1 801 877 8154

Aaron L. Nielson

Practices

Overview

Aaron Nielson is of counsel in the Washington, D.C., and Salt Lake City, Utah offices of Kirkland & Ellis LLP, focusing primarily on appeals, antitrust, and administrative law matters, as well as other questions of law arising in complex litigation. Aaron has particular experience regarding petitions for review of agency rulemakings and the intersection of antitrust and intellectual property, as well as multi-district litigation. In 2020, the U.S. Supreme Court appointed Aaron to brief and argue a separation-of-powers dispute involving financial regulation.

Aaron serves as a public member of the Administrative Conference of the United States, a federal agency that studies the administrative process and makes recommendations on ways to improve it. He also serves on the Council of the American Bar Association’s Section of Administrative Law & Regulatory Practice. Previously he chaired or co-chaired the Section's Rulemaking and Antitrust & Trade Regulation Committees. In recent years, Aaron has been invited to present on rulemaking at both the Federal Trade Commission and the U.S. Department of Justice and his scholarship has been published in the journal of the American Academy of Arts and Sciences.

Earlier in his career, Aaron served as a clerk to Justice Samuel A. Alito, Jr. of the U.S. Supreme Court, Judge Janice Rogers Brown of the U.S. Court of Appeals for the D.C. Circuit, and Judge Jerry E. Smith of the U.S. Court of Appeals for the Fifth Circuit.

Administrative Law and Statutory Appeals

  • Collins v. Yellen, 141 S. Ct. 1761 (2021): Appointed by U.S. Supreme Court to brief and argue in defense of an act of Congress. 
  • Horne v. Dep't of Agriculture, 133 S. Ct. 2053 (2013): Obtained unanimous U.S. Supreme Court decision allowing raisin farmers to challenge the constitutionality of a federal marketing order.
  • Compucredit Corp. v. Greenwood, 132 S. Ct. 665 (2012): Secured U.S. Supreme Court decision upholding enforceability of arbitration clauses for claims brought under the Credit Repair Organizations Act.
  • PLIVA, Inc. v. Mensing, 131 S. Ct. 2567 (2011): Obtained U.S. Supreme Court decision holding that the Hatch-Waxman Act and associated FDA regulations preempt state-law tort claims targeting generic pharmaceutical products.
  • Dow AgroSciences LLC v. National Marine Fisheries Serv., 707 F.3d 462 (4th Cir. 2013): Secured decision vacating an agency’s biological opinion as arbitrary and capricious.
  • Dow AgroSciences LLC v. National Marine Fisheries Serv., 637 F.3d 259 (4th Cir. 2011): Obtained reversal of district court decision refusing to exercise jurisdiction over client’s administrative law challenge to federal agency’s Biological Opinion.
  • Apotex, Inc. v. Sebelius, 384 Fed. App’x 4 (D.C. Cir. 2010), cert. denied. (Jan. 18, 2011): Successfully intervened and defended client’s 180-day marketing exclusivity under the Hatch-Waxman Act.
  • Teva Pharms. USA, Inc. v. Sebelius, 595 F.3d 1303 (D.C. Cir. 2010): Obtained pre-enforcement review and secured injunctive relief precluding FDA from denying client 180-day Hatch-Waxman exclusivity.

Antitrust

  • Eatoni Ergonomics, Inc. v. Research In Motion Corp., 826 F. Supp. 2d 705 (S.D.N.Y. 2011), aff’d, 486 Fed. App’x 186 (2d Cir. 2012): Obtained dismissal with prejudice of claim of alleged monopolization in case raising patent infringement, essential facilities, and duty to deal theories.
  • Represented Teva Pharmaceuticals in its successful $6.8 billion acquisition of Cephalon that was cleared with divestitures following a second request from the Federal Trade Commission.
  • Represented Chiquita in investigating and securing leniency from the European Commission in connection with bananas and pineapple price and volume information exchanges.
  • Silvious v. Chiquita Brands Int’s, Inc., (D.D.C 2010): Obtained dismissal with prejudice of putative representative action alleging price-fixing.

Honorable Samuel AlitoSupreme Court of the United States

Honorable Janice Rogers BrownUnited States Court of Appeals for the District of Columbia Circuit

Honorable Jerry E. SmithUnited States Court of Appeals for the Fifth Circuit

More

Thought Leadership

Recent Law Review Articles

Gaming Certiorari, 170 University of Pennsylvania Law Review (forthcoming 2022) (with Paul Stancil).

Deconstruction, Not Destruction, Daedalus: The Journal of the American Academy of Arts & Sciences (2021).

The Minor Questions Doctrine, 169 University of Pennsylvania Law Review 1181 (2021).

Three Wrong Turns in Agency Adjudication, 28 George Mason Law Review 657 (2021).

Narrowing Chevron’s Domain, 70 Duke Law Journal 931 (2021) (with Kristin E. Hickman).

Foreword: The Future of Chevron Deference, 70 Duke Law Journal 1015 (2021) (with Kristin E. Hickman).

How Agencies Choose Whether to Enforce the Law: A Preliminary Investigation, 93 Notre Dame Law Review 1517 (2018).

Optimal Ossification, 86 George Washington Law Review 1209 (2018).

Sticky Regulations, 85 University of Chicago Law Review 85 (2018).

Chevron Step One-and-a-Half, 84 University of Chicago Law Journal 757 (2017) (with Daniel Hemel).

Beyond Seminole Rock, 105 Georgetown Law Journal 943 (2017).

Other Publications

Developments in Administrative Law & Regulatory Practice 2014: Antitrust, American Bar Association (2015) (with Marin Boney & Varnitha Siva)

Developments in Administrative Law & Regulatory Practice 2014: Antitrust, American Bar Association (2014) (with Marin Boney & Brad Masters)

Whither Harmonization? India’s Draft Combination Regulations, CPI Antitrust Chronicle (2011) (with Christine Wilson & Ellen M. Jakovic)

Memberships & Affiliations

Public Member and Chair of the Administrative and Management Committee, Administrative Conference of the United States

Council, American Bar Association’s Section of Administrative Law & Regulatory Practice

Credentials

Admissions & Qualifications

  • 2016, Utah
  • 2010, District of Columbia
  • 2008, Arizona (inactive)

Courts

  • Supreme Court of the United States
  • United States Court of Appeals for the Third Circuit
  • United States Court of Appeals for the Fourth Circuit
  • United States Court of Appeals for the Fifth Circuit
  • United States Court of Appeals for the Sixth Circuit
  • United States Court of Appeals for the Eleventh Circuit
  • United States Court of Appeals for the Federal Circuit
  • District of Columbia Court of Appeals

Education

  • Harvard Law SchoolJ.D.magna cum laude2007
  • Faculty of Law, University of CambridgeLL.M.First Class Honors2006

    Elected a Bateman Scholar of Trinity Hall

  • University of PennsylvaniaB.A.summa cum laude2003

    Robert Holtz Memorial Award as Most Outstanding Graduating Senior in Political Science