Nelson Castellano is the firm’s Managing Shareholder, joining the firm in 1992. He previously co-chaired the Business Transactions Practice Group. Nelson’s practice focuses primarily on corporate and business matters, providing general business advice to emerging growth and middle market companies, capital raising transactions, including private placements of debt and equity and venture capital, mergers and acquisitions, and business formation and entity selection. His practice also includes venture capital transactions, purchase and sale transactions, compensation and equity arrangements, and securities law.

Honors and Distinctions

  • Honoree, Junior Achievement Hall of Fame Awards, 2022
  • Recipient, Junior Achievement of Tampa Bay’s Vanguard Award, 2022
  • Tampa Magazine’s Top Lawyers List, 2018, 2020-2024
  • AV® Preeminent Peer Review Rated by Martindale-Hubbell
  • The Best Lawyers in America, Corporate Law, Securities/Capital Markets Law, 2007-2024
    • Lawyer of the Year, Securities/Capital Markets Law, 2012, 2017, 2019, 2021-2022
  • Chambers USA Recognized Practitioner, Corporate/M&A, Private Equity, 2015-2020, 2022-2023
  • Florida Super Lawyers 2006, 2008-2023 (10+ year recognition)
  • Florida Trend’s Legal Elite, 2007, 2008, 2020, 2022
  • Recipient, Junior Achievement Bronze Leadership Award, 2007

Professional Involvement

  • American Bar Association
    • ABA Small Business Section Task Force on Private Placement Broker Dealer Registration, Co-Chair
  • The Florida Bar
  • Hillsborough County Bar Association
  • Vistage Group 2095, Member, 2002-present
  • Florida Venture Forum
    • Board Member, 2007-present
    • Executive Committee, 2016-present
  • Young Presidents Organization (YPO), Member, 2010-present

Community Involvement

  • Tampa Bay WaVE, Board Member, 2015-present
  • Lowry Park Zoological Society, Board of Trustees, 2016-present
  • Association for Corporate Growth Tampa Bay
  • Junior Achievement of Tampa Bay, Board Member, 1996-present


Thought Leadership

  • “Trenam’s new top executive Nelson Castellano shares his vision on the firm’s next generation of growth,” Tampa Bay Business Journal, September 2023
  • “Exclusive: Longtime Trenam attorney to succeed Marie Tomassi as managing shareholder,Tampa Bay Business Journal, September 2023
  • “The Bridgevine Story,” Panelist, Florida Venture Forum 29th Annual Florida Venture Capital Conference, January 30, 2020
  • “What Does a Venture-Backed Company Look Like?” Florida Venture Forum Venture Capital Bootcamp, September 29, 2015
  • Florida Limited Liability Company Forms and Practice Manual, co-author with Al O’Neill and Tate Taylor, Data Trace Publishing Company
  • “Company Valuations: What is My Company Worth and How is That Determined?”, Florida Venture Forum and Gulf Coast Venture Forum
  • “Negotiating the Venture Capital Investment Term Sheet,” Florida Venture Forum
  • “Entity Choice – Consequences and Selection,” ABA Section of Business Law Spring Meeting
  • “Key Issues in Negotiating Acquisition Agreements,” Florida Bar Association
  • “From No Dough to Cash Flow,” Florida Venture Forum
  • “Closing the Deal: Negotiating the Capital Investment Term Sheet,” Florida Venture Forum
  • “Tax Planning Considerations When Buying or Selling a Business,” Florida Bar Association
  • “Securities Law Developments,” Hillsborough County Bar Association
  • “Best Practices that Drive Growing Companies,” The Executive Committee
  • “Business Succession Planning in Florida,” Lorman Education Seminars