Susan Antonio


Attorney, Member of the Firm
Office Phone: 617-429-8012 
Email: santonio@outsidegc.com

Susan M. N. Antonio joined Outside GC in 2014, bringing over 30 years of experience in corporate and securities law, venture capital, business development, financial operating, tax and public accounting. She has worked with companies at various stages of development, across a range of industries, including arts and entertainment, biotechnology, e-commerce, cannabis, financial services, health care, information technology, life science, professional services and software. Her clients at Outside GC include Alternative Compassion Services Incorporated, Censa Pharmaceuticals Inc., Fresh Source Capital, LLC, HawkPartners, LLC, and Livelife Capital Partners LLC

As an advisor to many start-up and emerging businesses, Susan regularly works with founders on entity formation, business plan creation, compensation arrangements and financing strategies for angel, seed and venture investments. Susan also works closely with business and functional teams, advising on day-to-day legal and operational issues, as well as strategic and transactional matters, such as commercial contracts, joint ventures, mergers and acquisitions and strategic alliances. She has drafted, reviewed, and negotiated a wide range of contracts and agreements, including corporate governance agreements, operating agreements, convertible notes and purchase agreements, stock and asset purchase agreements, investment agreements including voting agreements, investor rights agreements and right of first refusal and co-sale agreements, letters of intent, sales contracts, master services agreements, employment agreements, consulting agreements, benefit agreements, bonus and commission plans, and placement agreements.

Prior to Outside GC, Susan served for thirteen years as Chief Legal Counsel and General Partner of Saturn Partners, a Boston-based venture capital firm, where she handled legal and operational matters for Saturn and its affiliates.  She also advised Saturn’s portfolio companies on the myriad legal and financial issues associated with developing early stage companies and commercializing technologies. Susan formed and managed three venture capital limited partnerships, special opportunity investment vehicles and their related general partner and management companies. She also structured and negotiated over $145 million of debt and equity investments in a broad range of industries.

From 1996 to 2000, Susan practiced corporate and securities law with Bingham McCutchen LLP, an international law firm, where her clients included an electronic commerce issuer in a $50 million initial public offering and $40 million stock-for-stock acquisition; a biotechnology issuer in a $17 million initial public offering; and a corporate issuer in a $20 million private placement of convertible preferred stock.

From 1980 to 1987, Susan worked in public accounting as an auditor and tax practitioner, completing her tenure as a tax manager with Ernst & Young LLP in Boston. From 1987 to 1993, she held senior financial operating positions in several early and later stage development companies.

Susan is the Founder of Impactive Strategic Investments LLC, a social venture-focused consulting firm that leverages her expertise in venture capital in the development and advancement of socially motivated for-profit and nonprofit organizations, particularly those utilizing education technology and advancing STEM initiatives. She is a member of the Parents Committee of the Boston Latin School Association.

Susan holds a Juris Doctor degree from the University of Miami School of Law, where she was Senior Articles Editor of the University of Miami Law Review and a member of the Order of the Coif. She also holds a MS degree in Taxation from Bentley College and a BS degree in Business Administration from Boston College.