EST. 1987 · NEW YORK · SAN FRANCISCO · LONDON
For thirty-seven years, Halstead & Voss has represented companies and individuals in the matters that define them. We don't measure success in billable hours — we measure it in relationships that span decades.
— PRACTICE AREAS
Six core areas. No dilution of focus. We staff each matter with partners who have litigated, negotiated, or closed in that specific field for at least fifteen years.
Breach of contract, partnership disputes, business torts, and trade secret claims. Tried in federal and state courts across 19 jurisdictions. Recent win: $94M jury verdict for a software client.
19 jurisdictions · Federal & StateFrom incorporation to exit. M&A advisory, due diligence, deal structuring, and post-merger integration. $4.6B in aggregate deal value over the last five years across 73 transactions.
73 deals · $4.6B aggregatePatent prosecution, trademark portfolios, copyright enforcement, and licensing. We hold registered patent agent credentials and have filed in 40+ countries via our PCT practice.
40+ countries · PCT practiceSEC enforcement, FTC matters, antitrust review, and internal investigations. We build compliance programs that hold up under government scrutiny — not just on paper.
SEC · FTC · DOJ experienceExecutive contracts, non-compete enforcement, wrongful termination defense, and workplace investigations. Counsel for both employers and senior executives — never both in the same matter.
Employer & Executive counselInbound and outbound deals involving EU, UK, APAC, and LATAM jurisdictions. We coordinate with trusted local counsel in 22 countries — and we've worked with most of them for over a decade.
22 countries · 4 regions— THE FIRM
Halstead & Voss was founded in 1987 by Margaret Halstead and Adrian Voss — two federal prosecutors who believed private practice could be conducted with the same rigor, candor, and sense of public duty they brought to government service.
Thirty-seven years later, that standard still defines us. We don't take every case. We don't staff matters with associates learning on your dime. And we don't settle for outcomes that look good in a press release but fall apart under scrutiny. Our average client relationship spans 11 years — because the counsel we give in year one is designed to still hold up in year ten.
We accept fewer matters so each gets the attention it deserves.
We tell you what you need to hear, not what makes the meeting easier.
Most matters are handled on fixed-fee or capped-fee arrangements.
— ATTORNEYS
Not a rotation of faces. When you engage Halstead & Voss, you work directly with a named partner from the first call through resolution. Here are four of them.
Founding Partner · Commercial Litigation
Former Assistant U.S. Attorney, Southern District of New York. 37 years of trial experience. Tried 42 cases to verdict with a 78% win rate. Fellow, American College of Trial Lawyers.
Partner · Corporate & M&A
Former M&A associate at Sullivan & Cromwell. Led 73 transactions totaling $4.6B in deal value. Dual-qualified in New York and England & Wales. Speaks Russian, French, and Mandarin.
Partner · Intellectual Property
Registered patent agent (USPTO). PhD in electrical engineering, Stanford. 120+ patents prosecuted. Lead counsel in the landmark Sequoia Systems v. Apex patent case — $31M verdict.
Partner · Regulatory & Compliance
Former SEC enforcement attorney, Division of Enforcement. Built internal investigation practices for three Fortune 100 companies. Recognized by Chambers USA for regulatory defense since 2019.
— REPRESENTATIVE MATTERS
A selection of publicly disclosable matters. Most of our work is confidential — but these illustrate the scale and stakes we operate at.
Represented a software infrastructure company in a three-week federal jury trial against a former partner who misappropriated proprietary architecture. Verdict included $31M in compensatory and $63M in punitive damages. Affirmed on appeal, Second Circuit, 2022.
Lead counsel for a European acquirer in a cross-border purchase of a U.S. AI platform. Navigated CFIUS review, EU merger control, and concurrent IP litigation in three jurisdictions. Closed in 9 months.
Represented a public company CEO in a 14-month SEC investigation into revenue recognition practices. After full internal investigation and Wells submission, the Staff issued a no-action recommendation. Zero penalties, zero restatement.
— CONTACT
All initial consultations are privileged and without obligation. We respond to inquiries within four business hours. If your matter is urgent, call our after-hours line directly.
420 Lexington Avenue, 34th Floor
New York, NY 10170
555 California Street, Suite 1200
San Francisco, CA 94104
1 King Street, Mayfair
London W1J 5DD, UK
New York: (212) 555-8700
After-hours: (212) 555-8799
Your inquiry has been routed to the appropriate partner. We will respond within four business hours. For urgent matters, call (212) 555-8799.