Law Firm “Hung Client Out to Dry” through Undocumented Representation

University of Miami School of Law ethics professor testified that Simpson Thacher & Barlett LP committed professional negligence and legal malpractice when creating an opinion letter for Patriot National attributed to its owner, Steven Mariano, to close a $50 million private investment in public equity (“PIPE”) deal. When the terms of the deal went public, Patriot National’s stock dropped by 40 percent, and PIPE investors were entitled to further shares to make up their investment under Series B Warrants. Patriot National and its main customer, workers' compensation insurer Guarantee Insurance Co.--both of which Mariano majority-owned--declared bankruptcy within three years of the deal.

The ethical violation, Professor Anthony Alfieri testified, was that no written agreement between Simpson Thacher & Barlett LP and Mariano (“Simpson Thacher”) existed clarifying their attorney-client relationship. Simpson Thacher itself, however, admitted it performed legal services on behalf of Mariano, though they were limited to the opinion letter. Moreover, no letter ever advised Mariano their relationship ended after Simpson Thacher’s draft of the opinion letter, which left Mariano vulnerable to risk without counsel representing him. Alfieri stated this conduct was, “hanging [Mariano] out to dry, and that's not consistent with our standards of professional conduct." Madison Arnold, Simpson Thacher Hung Client Out to Dry, Jury Hears, Law 360 (July 29, 2026).

Mariano alleges in his lawsuit Simpson Thacher put these companies out of business through its poor construction of the deal, entitling him to upwards of $100 million in relief. By forming an attorney-client relationship with Patriot National’s founder for the opinion letter—outside of their legal duties to the company itself in proctoring the deal—seemingly demonstrates negligence on behalf of Simpson Thacher when executing the PIPE transaction. Simpson Thacher continues to argue Mariano was never client of the firm, outside of the opinion letter, and owed no obligation to him. They reiterate, “We were willing to deliver an opinion because he had nobody else that would step up… [we] don't know whether there were any other formalities associated with it, but we were doing something to facilitate a transaction that we were working night and day on.” Id.

Nevertheless, the exchange between Simpson Thacher and Mariano serves as a powerful reminder to the statutory obligations of practitioners performing legal work on behalf of individuals within a larger corporate client and the diligent record-keeping required therein.