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Breton Leone-Quick


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Bret has significant experience litigating cases, and also guiding clients through disputes in a manner that helps them avoid litigation.  Bret serves as a trusted advisor to numerous public and private company board of directors, and counsels them on all aspects of fiduciary duty and corporate governance issues.  His understanding of the federal securities laws and experience with Delaware corporate law allow him to navigate clients through complex crises, disputes, and litigation.  He has extensive experience litigating and advising clients with respect to shareholder disputes, and has successfully served as trial counsel in “bet-the-company” cases, involving claims with a total value in excess of $1 billion.   

Bret also has extensive experience advising clients in the financial services sector, including investment banks, private equity sponsors, hedge fund managers, broker-dealers, placement agents, investment advisers, transfer agents, and FINTECH clients.  Bret represents these clients both with respect to litigation, and with respect to investigations by the government, including the USAO, SEC, FINRA, and Massachusetts Securities Division.  He has also led and participated in numerous internal investigations, including investigating foreign subsidiaries of U.S. companies.    

Bret actively represents clients (on both the buy-side and sell-side) on post-closing disputes in connection with merger or stock purchase transactions, and involving indemnification claims and claims for purchase price adjustments or earn-out payments.  Bret also enjoys working with entrepreneurs and start-up companies, and advising them on commercial disputes and risk management issues that they face as they seek to grow. 

Bret helps coordinate Mintz’s Global Anti-Money Laundering practice, and contributes to the drafting and editing of Mintz’s quarterly newsletter, co-published with its client Pegasystems,  International AML Highlights for Client OnBoarding.


Recent Trial Experience

Securities Law and Financial Services Litigation Experience

  • Successfully represented the CEO of a biotech company in a purported securities class action by defeating class certification.  In re Organogeneisis Sec. Litig., 241 F.R.D. 397 (2007).
  • Negotiated a dismissal (without any payment by client) of all claims brought against broker-dealer client in connection with the sale of interests in various hedge funds that turned out to be feeder funds into the Tom Petters Ponzi scheme.
  • Obtained summary judgment on claims brought by broker-dealer client against hedge fund manager for non-payment of fees earned for raising over $100 million in capital for the hedge fund.
  • Represented founder of a hedge fund in litigation against the seed investors in the hedge fund’s management company.  Negotiated a favorable settlement on the eve of trial.
  • Represented hedge fund client in dispute against former auditors for professional malpractice.  Negotiated a favorable settlement on behalf of the client.
  • Obtained the dismissal of most claims brought against a distributor of variable annuities by a client alleging various claims in connection with his purchase of a variable annuity.  Negotiated a favorable settlement on the remaining claims.
  • Represented Belgian bank Dexia S.A. in a securities class action suit that was ultimately settled.
  • Represented a client defrauded in the purchase of various securities, and obtained return of the entire investment from defendant shortly after filing the complaint.
  • Represented an investment advisor in litigation brought by a customer alleging fraud and unsuitability in a matter of first impression under various aspects of the Massachusetts Securities Laws.
  • Represented online lending platforms in litigation, including litigation involving state usury laws, and the “true lender” doctrine.

Other Significant Litigation Experience

  • Obtained dismissal of all claims at the pleadings stage in False Claims Act case brought against a large, regional pharmaceutical chain.  U.S. et al., Ex Rel. Thulin v. Shopko Stores Operating Company, LLC, No. 10-cv-196-WMC (W.D. Wis.).  Successfully represented the client on appeal with the appeals court affirming the dismissal of all of the claims against the client.  Thulin v. Shopko Stores Operating Company, LLC, No. 13-3638 (7th Cir. Nov. 12, 2014).
  • Obtained a complete dismissal of a $360 million class action lawsuit alleging violations of RICO and the laws of over 25 states brought against one of the nation’s leading laboratories.  International Brotherhood of Teamsters Local 456 Health and Welfare Trust Fund v. Quest Diagnostics Inc., Civil Action Not. 10-CV-1692 (E.D.N.Y.).
  • Represented insurance agency in a data breach case.  Obtained dismissal of all claims at the pleadings and summary judgment stages; after one claim was restored on appeal, negotiated a favorable settlement on behalf of the client a week before trial.
  • Served as trial counsel for a real estate broker seeking to recover its commission in connection with brokering the sale of a multi-million dollar multi-unit apartment and condominium development.  Achieved a settlement for nearly the entire amount of claimed damages after just a couple of days of trial.
  • Represented a company and its majority owner against a minority investor alleging fraud, and seeking a larger equity stake in the company.  Successfully obtained dismissal at the pleadings stage of certain claims, and then settled the remaining claims on favorable terms.

Internal Investigations

  • Represented the audit committee of a public company that manufactured and sold medical devices in an internal investigation of various accounting issues, and led the investigation of the company’s Brazilian subsidiary.
  • Represented the board of a private company in conducting an internal investigation into allegations of misconduct by the company’s CEO.
  • Conducted an internal investigation into allegations of scientific fraud at a public company that were raised by a former employee and purported whistle-blower.

Regulatory Investigations

  • Represented a CEO of an acoustics company in an SEC investigation.  Prepared a successful “Wells” submission on behalf of the client that resulted in no charges being brought against the client.
  • Represented a registered investment advisor in SEC investigation alleging breach of fiduciary duty with respect to a client account.  Persuaded the SEC not to bring charges through a “Wells” submission.
  • Represented the CFO and controller of a company in an SEC investigation relating to an allegedly false registration statement for an IPO.  Clients were not charged by the SEC.
  • Represented company in an SEC investigation involving the authorization of allegedly false confirmations issued by a retailer.  The SEC did not bring charges against the client.
  • Represented director of company in the Cleantech industry in an SEC investigation.  No charges were brought against the client.
  • Represented broker-dealer in SEC and DOJ investigations into the Petters Ponzi scheme.  No charges were brought against client.
  • Represented portfolio manager of a major financial institution in an SEC investigation involving exposure to auction rate securities.  No charges were brought against client.
  • Represented the former CFO of a public company in an SEC and DOJ investigation, and helped the client avoid a criminal indictment, and negotiated a favorable SEC settlement on his behalf.
  • Represented the former CFO of a public company in an SEC investigation into stock options backdating, and helped the client avoid criminal charges while settling the SEC action. 
  • Represented the former officer of a mutual fund adviser in an SEC investigation involving market timing, and negotiated a settlement that allowed the officer to remain in the industry.
  • Represented a major investment bank in investigation by Massachusetts Securities Division with respect to its role in a merger of public company based in Massachusetts.  Client was not charged by the Securities Division.
  • Represented an investment advisor in a proceeding before the Massachusetts Securities Division involving registration issues, and negotiated a favorable settlement.
  • Represented the distributor of variable annuities in investigations by the SEC and Massachusetts Securities Division, and helped negotiate a favorable global settlement.
  • Represented broker-dealer and registered representative in Massachusetts Securities Division investigation and NASD arbitration brought by a customer alleging unsuitable investments.  The Massachusetts Securities Division did not bring charges against the client, and the NASD arbitration was settled without any payment by the registered representative.
  • Led investigation for the Audit Committee of a leading medical device company into financial reporting, regulatory compliance issues, and allegedly corrupt practices in business units on four continents. Supervised accounting restatement of distributor transactions and reserves over several reporting years.
  • Favorably settled a dispute arising out of undue influence and other trust and estate related issues between family members.
  • Won a complete dismissal of a $360 million class action lawsuit alleging violations of RICO and the laws of over 25 states brought against one of the nation’s leading laboratories.
  • Represented a digital solutions company in connection with noncompete related employment disputes with its former employees and its competitor. Mintz successfully acquired first a temporary restraining order and then a preliminary injunction order to enforce the confidentiality, nonsolicitation, and noncompetition provisions in the employee agreements those employees had entered with the company.
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Public companies need to consider regulatory, legal, market, and ESG-related developments in preparing for their fiscal year-end filings with the SEC and their annual shareholder meetings. In an in-depth memorandum, Mintz attorneys discuss the SEC’s new cybersecurity disclosure rule, recent trends in reverse stock splits, and the SEC’s disclosure requirements for Rule 10b5-1 trading plans and insider trading policies, and other emerging issues affecting public companies.

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Read about key regulatory and other developments, including board diversity and other ESG matters, which public companies need to consider as they prepare for their fiscal year-end SEC filings and 2022 annual shareholder meetings.
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Bret Leone-Quick discusses the trends that have emerged with respect to the types of claims being asserted in securities class actions against life sciences companies.
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Bret Leone-Quick discusses implications of the Supreme Court’s decision in Cyan, Inc. v. Beaver County Employees Retirement Fund in which the Court ruled that claims arising under the Securities Act of 1933 can be brought in a class action format in state court.
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As our clients and friends know, each year Mintz Levin provides an analysis of the regulatory developments that impact public companies as they prepare for their fiscal year-end filings with the Securities and Exchange Commission (“SEC”) and their annual shareholder meetings.
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Our Venture Capital & Emerging Companies practice group analyzed the SEC's recently released equity crowdfunding rules (referred to by the SEC as "Regulation Crowdfunding") in a concise and easy-to-digest article authored by Sam Effron and Kristin Gerber.
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As originally reported on our Privacy & Security Matters blog, Mintz Levin will sponsor a webinar on September 30 at 1:00 p.m. (ET) to address regulatory compliance and risk management aspects of cyber attacks and data breaches at financial institutions and their service providers.
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Mintz Levin’s Institutional Investor Class Action Recovery practice recently launched a new blog: Class Action Recovery for Mutual Funds.  This new blog will report on various happenings in class action cases that may not be covered in other securities litigation blogs or publications, and that will be of special interest to institutional investors.
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A recent decision by Judge F. Dennis Saylor of the U.S. District Court for the District of Massachusetts, Butler v. Moore, C.A. No. 10-10207-FDS U.S. Dist. LEXIS 39416 (D. Mass. Mar. 26, 2015), offers an example of how fiduciary duties can continue to govern the conduct of participants in a closely held corporation or LLC under Massachusetts law, even where parties claim that those duties have been abrogated by contractual agreement. 
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News & Press

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Mintz is pleased to announce that 120 firm attorneys have been recognized as leaders by Best Lawyers® in the 2024 edition of The Best Lawyers in America©.

This in-depth article discusses the closely-watched Akorn, Inc. v. Fresenius Kabi AG lawsuit. The decision, allowing a German drug company to pull out of $4.75 billion deal to acquire a U.S. competitor, came from the Delaware Chancery Court – a key voice for businesses and their attorneys. Mintz Members Bret Leone-Quick and Matt Tikonoff are quoted extensively throughout the article providing third-party commentary.
Mintz represented Right Networks in selling a controlling interest in the company to BV Investment Partners, a middle-market private equity firm focused on the business services and IT services sectors. 
Mintz Members Thomas Burton and Breton Leone-Quick helped author SEC Compliance Best Practices, 2016 ed., in which “expert lawyers offer guidance on the various regulations and latest trends” pertaining to the SEC and their impact on companies and their counsel.
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Events & Speaking


The Risk Management Society

Securities Fraud Litigation and the D&O Insurance Market

Boston Convention Center, Meeting Room 052 A – Exhibit Level

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Recognition & Awards

  • Best Lawyers in America: Commercial Litigation (2024)

  • The National Law Journal and Connecticut Law Tribune: Rising Star (2014)

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  • Co-Editor, American Bar Association Securities Litigation Journal
  • Co-Editor, Securities Litigation & Compliance Matters blog
  • Member, Community Impact Committee, United Way of Massachusetts Bay and Merrimack Valley
  • Clerk, Board of Directors, Lexington Youth Lacrosse
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