Sonenshine Partners Research
Overview & Advisory Approach
Sonenshine Partners is a boutique global investment banking firm founded in 2000 by Marshall Sonenshine, a veteran M&A banker with deep experience across major Wall Street institutions. Headquartered at 505 Park Avenue in New York with offices in London and affiliates across Europe and Asia totaling 250+ personnel, the firm operates with a thesis-driven approach to complex, cross-border transactions. The firm's core philosophy centers on institutional-quality execution combined with personal leadership — senior dealmakers with 30+ years of experience directly engage on every transaction, bringing deep sectoral knowledge and extensive buyer networks.
Sonenshine Partners specializes in complex M&A advisory, corporate finance, and restructurings for Fortune 500 companies, middle-market businesses, and financial sponsors. The firm has been named "Boutique Bank of the Year" by M&A Advisor and serves as the sole U.S. Partner to Advior International, a premier consortium of leading investment banks across Europe and Asia with 1,400+ completed M&A transactions.
Sector Expertise & Deal Track Record
Sonenshine has accumulated a diverse portfolio of transaction experience across multiple verticals, demonstrating particular depth in three signature sectors: media & entertainment, healthcare (especially optical), and technology.
Media & Entertainment: The firm's media practice includes marquee transactions such as advising 21st Century Fox on the $3.5 billion merger of Shine Group with Apollo Management portfolio companies Endemol and CORE Media; the $3.3 billion sale of Warner Music Group to Access Industries; the $820 million sale of NEP Broadcasting by American Securities; the $900 million acquisition of DreamWorks film library by Dune Capital Management; and the sale of film finance company RatPac-Dune Entertainment to Warner Bros. The firm also advised Philadelphia Media Holdings on a $139 million bankruptcy sale, which was the highest price paid for a U.S. newspaper chain during the 2009-2012 distress period.
Healthcare & Optical: Sonenshine maintains exceptional depth in healthcare transactions, with the London-based Sonenshine Fulford Group (a co-advisory relationship with The Fulford Group) led by Dr. Wilder Fulford, who has completed over 100 financing and M&A transactions worth over $100 billion. The firm advised on the $900 million sale of 1-800 CONTACTS to WellPoint (now Anthem); the sale of IRIS The Visual Group (Canada's leading eye care chain) to New Look Vision Group for $120 million; the $350 million sale of Optical Distributor Group to ABB-Concise; the acquisition of TruHearing by EQT-backed Sivantos Group; and the acquisition of 1-800 CONTACTS assets by Menicon. Vision Direct was sold to Essilor International. The firm advised on various other optical retailer and distributor transactions with Luxottica, Essilor, and ABB-Concise.
Technology & Software: The firm has deep expertise in enterprise software and digital businesses. Notable transactions include the $190 million sale of Incadea (automotive dealer management software) to Dealertrack Technologies; the $425 million sale of ABAQUS (simulation and visualization software) to Dassault Systèmes; and the $3.5 billion merger of Shine Group combining media technology and production capabilities.
Consumer, Manufacturing & Diversified: Additional transactions include the $450 million sale of drugstore.com to Walgreens (representing a 113% one-day premium to stock price); the divestiture of SkinStore.com by Walgreens to the Hut Group; the $175 million acquisition by Chinese containerboard producer Nine Dragons Paper of the Rumford and Biron pulp mills from Catalyst Paper, marking the firm's successful cross-border advisory to Chinese publicly-listed companies; the sale of Structural Dynamics to EDS; and the sale of Anne Lewis Strategies (tech-enabled digital fundraising services) to Stone-Goff Partners.
Buyer Network & Transaction Characteristics
Sonenshine's deal flow reflects strong relationships with leading private equity firms including Audax Group, Genstar Capital, KKR, Bain Capital, New Mountain Capital, Fenway Partners, and Apollo Management. The firm works extensively with strategic acquirers including Fortune 500 corporations, publicly-listed companies, family offices, and international conglomerates. Cross-border transactions are a particular strength, with advisory mandates spanning North America, Europe, and Asia-Pacific. The firm has completed 65+ transactions according to PitchBook, with experience across sell-side M&A, buy-side advisory, recapitalizations, and bankruptcy restructurings.
Process & Fee Structure
Sonenshine emphasizes institutional-quality process management and direct senior banker involvement. The firm typically manages structured auction processes with targeted buyer outreach, comprehensive quality-of-earnings support, management coaching, and data room preparation. Engagement timelines vary based on transaction complexity but typically span 4-9 months from retention to close. The firm structures engagements with retainers (credited against success fees) and success fees based on negotiated deal-specific terms. Minimum engagement sizes typically reflect the firm's focus on meaningful transactions where full institutional process delivers value.
Geographic Coverage & Offices
The firm operates from New York headquarters with established offices in London and affiliate relationships across Europe (especially Germany and France), and Asia-Pacific (Japan, China, Hong Kong, Singapore). This geography supports both domestic U.S. M&A and cross-border transactions.
Competitive Positioning
Sonenshine differentiates through: (1) senior banker engagement across all transactions; (2) deep sectoral expertise developed over 20+ year careers by managing directors; (3) institutional process rigor; (4) extensive buyer networks spanning PE, strategic, and international buyers; (5) FINRA broker-dealer registration enabling integrated advisory and capital markets capability; and (6) cross-border transaction experience. The firm is recognized as a leader in sectors like optical distribution, media M&A, and healthcare transactions.
Team & Leadership
The firm's leadership team includes Marshall Sonenshine (Chairman, Managing Partner, Founder), a former Global Co-Head of M&A at Deutsche Bank with deep experience from Salomon Brothers, Wolfensohn & Company, and Bankers Trust. Senior Managing Directors Elliott K. Slade III (20+ years at BT Wolfensohn, Deutsche Banc Alex. Brown) and Neil P. Benedict (former Managing Director at Salomon Brothers, Dillon Read) bring extensive international and capital markets expertise. Dr. Wilder Fulford leads the London office with 25+ years of healthcare M&A experience. Managing Director Adam Greenberg brings $20 billion in transaction experience from roles at Kidder Peabody, UBS, Merrill Lynch, and AGM Partners media boutique. Director Jeff Klein (Sonenshine Fulford Group) has advised on 39 transactions worth $11 billion+. The team is rounded out by Vice President George Tagaris and Analysts including Gabriel Rodan and Brayden Mellick.