Before retiring in 2023, David A. Westenberg was a leading corporate and capital markets lawyer who spent more than four decades advising software, internet, and information technology companies. After joining WilmerHale in 1983, he guided numerous startups from formation through venture financings and ultimately to acquisitions or initial public offerings. As outside corporate counsel to both public and private companies, he advised clients on a wide range of corporate, securities, disclosure, and governance matters. His transactional experience included more than 50 IPOs and other capital markets transactions, along with extensive venture capital financings and mergers and acquisitions.

Mr. Westenberg was widely recognized for his deep understanding of the IPO market. He authored Initial Public Offerings: A Practical Guide to Going Public, published by the Practising Law Institute—a comprehensive resource praised for its practical insight and described by The New York Times as the “bible of the IPO market.” He wrote frequently on IPO and venture capital trends and was featured in publications such as The Wall Street Journal, Investor’s Business Daily, The American Lawyer, The Boston Globe, and Boston Business Journal. He was also active in the technology and legal communities, participating in technology councils and serving as a former co‑chair of the Boston Bar Association’s Corporate Law Committee.