About
Cassie L. Barr is an attorney who counsels clients on corporate and tax law matters. Her corporate work includes mergers, acquisitions, joint ventures, strategic alliances, business succession, private equity, and governance issues. She advises middle-market companies in health care, technology, construction, manufacturing, and distribution. Her guidance helps clients structure transactions, plan growth, manage tax concerns, and resolve complex business decisions with practical legal judgment and steady support across industries.
Cassie earned her J.D. from Saint Louis University School of Law, with concentrations in Business Transactions and Taxation. She also holds an M.B.A. from Southern Illinois University Edwardsville. She earned her B.S., cum laude, in Accounting from Southern Illinois University Edwardsville. Her education supports her work in corporate planning, mergers, acquisitions, tax law, financial analysis, business organizations, and client counseling.
Cassie has experience representing owners, companies, and nonprofit organizations in business transactions and tax matters. She has assisted with sales and equity rollovers involving manufacturing, distribution, transportation, and private equity buyers. Her background also includes international tax work for a major professional services firm. She represents clients before the Internal Revenue Service and state taxing authorities, helping them address tax controversy matters and business planning needs with careful legal strategy.
Cassie L. Barr is recognized for work in business organizations, tax law, corporate transactions, and mergers and acquisitions. Her honors include Best Lawyers recognition and Legal 500 recognition for corporate and M&A matters. She focuses on clear communication, careful drafting, and practical solutions. Her work helps clients evaluate risks, complete transactions, protect business interests, and plan for long-term success with steady legal guidance and care for clients and growing companies.
Law Office Affiliations
- Partner, UB Greensfelder LLP
- Member, American Bar Association
- Member, Bar Association of Metropolitan St. Louis
Licensed State
- Missouri
- Illinois
Education
- Saint Louis University School of Law
Juris Doctor (JD) - Southern Illinois University Edwardsville
Master of Business Administration (MBA) - Southern Illinois University Edwardsville
Bachelor of Science (BS)
Awards & Badges


- Banking & Finance
- Mergers & Acquisitions
- Tax
- Trusts




