Brien M. Wassner

BRIEN WASSNER is a global co-leader of Sidley’s Private Equity practice, a co-leader of the New York M&A and Private Equity group, and a member of the firm’s Executive Committee. Brien represents large cap and middle market private equity sponsors and other private capital investors and asset managers, as well as their portfolio companies, in connection with complex transactions including mergers, acquisitions, dispositions, financings and general corporate matters. He has extensive experience in domestic and cross border leveraged buyouts, take-privates, carve-outs, distressed investments, special situations and structured equity investments and joint venture transactions.

Brien’s clients include private equity funds, sovereign wealth funds, family offices, hedge funds, pension funds, venture capital funds and other sponsors and asset managers, financial institutions, public and private companies and their financial advisers.

Brien often advises clients on transactions that are multijurisdictional in nature and subject to complex regulatory regimes. Representative industries include financial services and insurance, software and technology, healthcare and life sciences, media, real estate, business services, retail and consumer products, manufacturing, logistics and transportation, telecoms, energy and infrastructure.

He is recognized by Chambers USA for Private Equity: Buyouts in New York (2022–2025). In the 2024 edition, clients praised Brien as “a true business partner who provides great advice” and for being “commercial, knowledgeable and a strong advocate for his client.”

Prior to joining Sidley, Brien was a partner at another global law firm in the firm’s Mergers & Acquisitions practice and was one of the leaders of its Private Capital Industry group.

• BBQGuys, a leading e-commerce retailer of outdoor living products, in its acquisition of Mont Alpi, a premium manufacturer of modular outdoor kitchen islands and grills.
• MarcyPen Capital Partners (MarcyPen) as lead investor, together with Brand Velocity Group (BVG), in a growth investment in The GLD Shop (GLD), a globally recognized jewelry brand.
• TowerBrook Capital Partners in multiple transactions, including: its strategic investment in Amylu Foods, its acquisition of CBTS from altafiber (formerly doing business as Cincinnati Bell); its investment in Battea Class Action Services LLC; its joint venture with Pennant Park Capital; its investment in CAVU Investment Partners; TowerBrook Capital Partners and Further Global Capital Management in connection with the take-private of ProSight Global, Inc.; its sale of Orchid Underwriters Agency, LLC (Orchid Insurance), to Brown & Brown, Inc. and the related carve out and disposition of certain affiliated businesses; its acquisition, with the Related Companies, of the Stonebridge Companies; its add-on acquisitions by Stonebridge Companies; and its joint venture with Newtek to acquire small-balance commercial real estate loans and conventional business loans.
• One Equity Partners, a middle market private equity firm, in connection with its investment in Brown & Root Industrial Services (“Brown & Root”) alongside partner KBR, and in Brown & Root’s acquisition of Specialty Welding and Turnarounds.
• EQT Private Equity in multiple transactions, including: its acquisition of PRO Unlimited; the acquisition by PRO Unlimited of Workforce Logiq; the acquisition by PRO Unlimited of outsourced workforce management provider Geometric Results, Inc.; its acquisition of XP Software Ltd.; its acquisition of Innovyze Inc. and combination with XP Software; the acquisition by Innovyze Inc. of EMAGIN; its US$1 billion sale of Innovyze Inc. to Autodesk; its acquisition of FocusVision Worldwide; the merger of its portfolio company, FocusVision, with Confirmit, a portfolio company of Verdane; and EQT Private Equity and Verdane Capital in their sale of Forsta to Press Ganey.
• Stone Point Capital in multiple transactions, including: its investment in IEQ Capital; the sale of Kensington Vanguard National Land Services to Truist Insurance Holdings, Inc.; its investment in R. Seelaus & Co. Inc.; its acquisition of American Mortgage Consultants; the sale of Hodges-Mace to Alight; the acquisition by American Mortgage Consultants of String Real Estate Information Services and Meridian Asset Services; the acquisition by SitusAMC of MBMS Inc.; and the acquisition by SitusAMC of Alan King & Company.
• Bridgepoint Capital in connection with several investments, including its investment in and subsequent sale of Blume Global to WiseTech Global; its investment in Cloudbees; and its investment in a pharmaceutical manufacturing business.
• Wafra Inc. in multiple transactions, including: its pending acquisition of Aquila Air Capital from funds managed by Warburg Pincus LLC; its joint venture with Trinity Industries, Inc.; its investment in Global Container International; investments in Digital Bridge and Vantage Data Centers, and various other investments in telecoms, operating real estate business and assets; data centers, aircrafts, solar and renewable energy platforms, financial services, SPACs, shipping and logistics companies.
• Global Container International (GCI), a leading lessor of marine intermodal containers, in its acquisition by Triton International Limited, the world’s largest lessor of intermodal freight containers, for a total transaction value of over US$1 billion.
• Northleaf Capital Partners in multiple transactions, including: its investments in a vacation rental, reservation and marketing business; a national healthcare provider; a technology-enabled vacation rental manager; a physician holding company; a national car wash holding company; a global provider of sustainable polymer material science solutions; and a waste management business.
• Verdane Capital in connection with the sale of Inriver AB to Thomas H. Lee Partners; and the business combination of Forsta Group with Press Ganey.
• Beach Point Capital Management in multiple transactions, including: its multi-jurisdictional financing of Cipriani USA, Inc. and its global affiliates to support Cipriani’s expansion; its investment in Moneygram Corp.; its investment in Cyxtera and the related business combination with Starboard Value Acquisition Corp. and Magnetar Capital, LLC; and several investments in the hospitality, gaming, entertainment and insurance sectors.
• Centerbridge Partners in connection with: GoHealth; and several investments in the financial services sector. 
• Brand Velocity Partners in several matters, including: the acquisition of SCORE® Sports, a designer, manufacturer, and seller of youth team sports uniforms and equipment and in connection with its portfolio company BBQGuys.
• Axar Capital Management in connection with its acquisitions of LiveStyle and ID&T; and its take private acquisition of StoneMor Inc.
• IEQ Capital in the acquisition of EPIQ Capital Group, an approximately US$5.3 billion multi-family office and investment firm.
• A consortium of equity investors, including APG Asset Management, MEAG (Munich Re’s asset manager acting for investors from within Munich Re Group) and Clal Insurance Company, to acquire a 100% equity stake in Astoria Energy I and a 55% equity stake in Astoria Energy II.
• A consortium, headed by APG Asset Management N.V. (APG), on behalf of the largest Dutch pension fund, ABP, and Australian Retirement Trust (ART), in the acquisition of Riverstone Holdings’ equity stake in Pattern Energy Group LP (pending).
• Ancala in the formation of short line rail specialist Phoenix Rail and in the subsequent acquisition by Phoenix Rail of Lehigh Valley Rail Management.
• DYNAmore in its sale to Ansys.
• The Special Committee of the Board of Directors of Purple Innovation, Inc. in its unsolicited takeover proposal from Coliseum Capital Management.