Overview

Nick wins cases for clients and helps them favorably resolve disputes, including complex partnership, corporate governance, finance, and deal disputes. As a first-chair trial lawyer who has tried more than 30 jury trials, bench trials, and arbitrations, when a rare business case goes to trial, other law firms and clients ask him to join or lead the trial team.

Nick splits his time between Barack Ferrazzano’s Minneapolis and Chicago offices, although he regularly appears in courts across the country. Nick's trial experience and litigation style make him well-suited to represent plaintiffs. In recent years, he has recovered more than $125 million for his clients. He also represents defendants; for example, he has defeated by early motion practice numerous class actions seeking to stop M&A transactions involving more than $1 billion in aggregate transaction value. He also defends individuals against government agencies in administrative hearings and civil trials.

Nick frequently represents clients in the financial industry, including hedge funds, private equity funds, and banks, as well as their owners or partners. In line with the firm’s reputation as a nationally pre-eminent real estate firm, many of these clients focus on commercial real estate.

Nick is passionate about the legal profession and trial practice. He has served on the faculty of the National Institute for Trial Advocacy (NITA), which is the country’s leading organization for trial skills training for practicing attorneys. Through other continuing education legal programs for attorneys, he has presented with judges and other attorneys on picking juries, examining witnesses, and litigation issues surrounding shareholder and deal disputes. He also teaches a law school class on litigation practice. Committed to pro bono work, his favorite trial story is when he defeated a slumlord and the judge cleared the courtroom because of the raucous cheering by the group of tenants and neighbors.

Credentials

Admissions

  • State of Illinois
  • State of Minnesota
  • U.S. District Court - District of Minnesota
  • U.S. District Court - Western District of Wisconsin
  • U.S. District Court - Eastern District of Wisconsin
  • U.S. Tax Court

Education

  • Northwestern University Pritzker School of Law, J.D., cum laude, 2009
  • University of Wisconsin-Madison, B.S., with distinction, 2005

Experience

Shareholder & Partnership Disputes

  • Represented owners, investors, joint venture partners, or controlling shareholders in more than 100 shareholder, LLC, and partnership disputes.
  • Engaged by attorneys and law firms in law firm partnership disputes, all of which were resolved on confidential and favorable terms.
  • Advised special committees of boards of directors in various matters, including internal investigations and responding to offers by interested directors and/or controlling shareholders.
  • Advised significant public company stockholders in proxy fights.
  • Represented numerous publicly-traded companies and/or their boards of directors in class action lawsuits alleging breach of fiduciary duty.
  • Advised majority ownership group of major professional sports team in dispute with minority owner, successfully resolved with confidential removal of minority owner.
  • Represented group of investors in private equity fund organized as an LLC who challenged wind up of LLC and distributions by the managing member. Resolved with confidential settlement by which clients received 50x greater amount than original final distribution.
  • Represented minority shareholder of real estate company who sued majority shareholder for breach of fiduciary duty. Majority shareholder agreed to settle dispute by selling their ownership interest to Nick's client for only half of the market value of those shares.

Transaction-Related Litigation

  • Represented numerous publicly-traded companies and/or their boards of directors in class action lawsuits filed to enjoin publicly-announced mergers. Defeated every claim through early motion practice.
  • Represented numerous buyers and sellers in post-closing disputes, including those relating to working capital adjustments, earnouts, and claims of breach of reps or warranties.

Private Equity

  • Represented SEC-appointed receiver of a registered investment adviser that managed several private equity funds, who was appointed after the embezzlement by a principal of the adviser of over $50 million of client assets, in various lawsuits and claims pursued by the receiver. Ultimately obtained judgments in amount exceeding $50 million.
  • Represented private equity company portfolio company in lawsuit regarding rights as a minority shareholder and whether a right of first refusal had been triggered. Favorably settled with payment to the client by the plaintiff that filed the case.
  • Represented group of investors in private equity fund who challenged wind up of fund and distributions by the general partner. Resolved with confidential settlement by which clients received 50x the final distribution originally provided to them.
  • Represented real estate private equity firm in a lawsuit filed against it by an investor regarding the accounting and allocation of investment losses. After a week-long trial, the jury awarded the plaintiff approximately 1/4 of the total amount lost on his investments in several funds managed by the private equity firm, which was only a fraction of his demand. On appeal, the state appellate court reversed the jury's award and granted judgment for the private equity firm client on all counts and awarded client its attorneys' fees.
  • Advise European private equity firm in various U.S. law matters regarding its various portfolio companies.
  • Represented plaintiff in an accounting malpractice lawsuit filed against an accounting firm in connection with the accounting firm's audit of several private equity funds. Favorably settled on the eve of the arbitration hearing.
  • Represented private equity firm sponsor and its officers who were sued for tens of millions of dollars under a variety of contract and tort theories by a hedge fund and foreign bank that entered into a joint venture with an affiliate of the PE sponsor, after many of the asset-based loans made by the joint venture defaulted.

Banks

  • Represented banks sued by customers in dozens of cases involving various claims relating to losses incurred by customers.
  • Represented bank directors in all types of shareholder lawsuits.
  • Represented hedge fund in claim against Goldman Sachs seeking the court to order Goldman Sachs to distribute more than $200 million to bondholders. Settled day before trial after the court denied Goldman Sachs’ motion for summary judgment.
  • Representation of a defendant bank in a putative class action filed in state court. The putative plaintiff class had invested approximately $10 million in a Ponzi scheme through self-directed IRAs for which the bank had acted as custodian. Motion to dismiss granted by trial court and affirmed on appeal.
  • Represented banks in several lawsuits concerning personal guarantees by real estate developers for commercial real estate loans in amounts as high as eight figures.
  • Represented outside directors of a failed bank regarding potential civil and criminal claims against them and in interviews conducted by the FBI, FDIC, and U.S. Department of Justice. Ultimately no charges or claims filed.
  • Representation of bank officers in FDIC enforcement actions.

Real Estate

  • Represented REITs and real estate investment companies in a variety of cases regarding deals that fell apart and where substantial escrow deposits were in dispute.
  • Represented REITs where buyers made claims for indemnification or breach of reps or warranties.
  • Represented hedge fund seeking modification of waterfall affecting distribution of hundreds of millions of dollars in CMBS transaction.
  • Represented REITs in several disputes regarding lease renewal provisions where tens of millions of dollars were at issue.

Bankruptcy

  • Represent both plaintiffs and defendants in dozens of bankruptcy avoidance claims (i.e., preference and fraudulent transfer claims).
  • On behalf of a Chapter 7 bankruptcy trustee, negotiated dozens of settlements of preference claims and fraudulent transfer claims against former insiders of the debtor company and its subsidiaries.

Miscellaneous Disputes

  • Represent plaintiffs and defendants in various industries in litigation involving alleged breaches of contracts.
  • Represent trustees of trusts and personal representatives of estates in litigation with beneficiaries.
  • Represent both plaintiffs and defendants in trade secret and non-compete lawsuits.

Newsroom

News

Publications

Recognitions

  • Best Lawyer, The Best Lawyers in America© (2023-2026) 
    • Commercial Litigation
    • Litigation - Banking and Finance
    • Litigation - Real Estate
  • Future Star, Benchmark Litigation (2020-2025)
    • 40 & Under List (2018-2023)
  • Minnesota Rising Stars, Super Lawyers (2015-2023)
  • Intern, Federal Magistrate Judge Sidney Schenkier, Northern District of Illinois
  • bl_callahan_2026
  • Benchmark Litigation Future Stars 2025

Organizations

  • Member, American Bar Association
  • Member, Chicago Bar Association
  • Member, Federal Bar Association
  • Member, Hennepin County Bar Association
  • Member, Illinois State Bar Association
  • Member, Minnesota State Bar Association
  • Member, Jessup International Law Moot Court Team
  • Phi Beta Kappa
  • Volunteer Attorney, Neighborhood Justice Center
  • Volunteer Attorney, Volunteer Lawyers Network
Quote

“One peer praises litigator and future star Nicholas Callahan as one of the best trial lawyers I’ve come across."

Benchmark Litigation
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