Who We Are

Oscar L. Garz

Oscar L. Garza is the principal owner of Oscar L. Garza & Associates, P.C. and co-founder of Tax Advisory Services Group, LLC. His practice focuses on federal and state motor fuel excise taxes and includes client representation before the IRS and state tax revenue departments. Oscar provides advice and counsel on the proper taxation of commodity transactions and provides tax registration services for clients doing business throughout the United States.

Oscar was formerly a Multistate Tax Director in the Houston, Texas office of Deloitte Tax LLP. He led the Firm’s excise tax practice. Oscar represented clients before the IRS and various state taxing authorities in registration matters and other excise tax issues. He was also the lead multistate Tax Director for mergers and acquisitions in the Houston office. Prior to joining Deloitte in 2005, Oscar served as Senior Tax Counsel for the Supply and Distribution Business (“Shell Pipeline”) for Shell in the US. Prior to this position, he was Associate General Tax Counsel responsible for federal and state tax compliance for Shell in the US. He was also responsible for providing multistate direct and indirect tax advice and counsel to all Shell businesses. Oscar joined Shell Oil Company in 1998 as the state tax director responsible for state income, franchise, sales, use, excise, motor fuels and property tax compliance, counsel and audit defense. From 1993 to 1998, Oscar was Director; Sales, Use and Excise Taxes for the General Electric Company (“GE”). In this capacity, he led a team of professionals responsible for providing transaction tax advice and counsel and audit defense for GE and GE Capital. Prior to joining GE, Oscar was a multistate tax manager for a Big 6 accounting firm in Houston from 1989 to 1993. During this time, Oscar was responsible for advising clients in all areas of state and local taxes. From 1981 to 1989 Oscar worked for Exxon Company USA in Houston. His last assignment at Exxon was state tax counsel. Prior to this position, Oscar worked in the state income tax compliance group and the property tax group. He also worked in the excise tax group responsible for payroll taxes.

Oscar is a 1981 graduate from the University of Texas at San Antonio where he received his BBA in accounting. He received his JD in 1988 from the University of Houston Law Center.

Oscar is a member of the State Bar of Texas. He is the founding Student Notes Editor of the ABA publication the State and Local Tax Lawyer and was selected as a Texas Rising Star Super Lawyer in 2004 by Law & Politics magazine.

Leanne Sobel

Leanne Sobel is a Senior Associate with Oscar L. Garza & Associates, P.C. With over 10 years of experience, Leanne focuses her practice on regulatory and transaction tax matters, and related U.S. Customs regulations, affecting trading of refined petroleum products and other energy commodities. Her tax practice covers all aspects of compliance with federal and state excise taxes including federal and state registrations, federal and state motor fuel excise taxes and environmental fees, federal biofuel tax credits and taxes and fees due on importation, including oil spill fees. In addition, Leanne advises clients on energy tax-related legislative and policy issues on Capitol Hill and in the executive branch.

In her U.S. Customs practice Leanne advises clients on matters relating to importing crude oil, petroleum products and biofuels into the United States, trade preference programs, Foreign Trade Zone issues and issues arising from the Jones Act rules regarding coastwise trade. Leanne’s experience also includes advising on U.S. trade and foreign policy, such as issues related to obtaining export licenses from the U.S. Bureau of Industry and Security to allow U.S. persons to export items that are subject to the export control regulations, compliance with the foreign assets control programs applicable to U.S. persons, extraterritorial sanctions laws and antiboycott laws. She has counseled firms regarding transactions and investments involving the governments, nationals and products of countries subject to trade sanctions and, where necessary, assisted them in obtaining licenses from the U.S. Department of Treasury to enter into transactions otherwise prohibited or with respect to blocked property.

Leanne graduated with honors from St. Anne’s College, University of Oxford where she received her JD and MA. She is a member of the New York Bar and the District of Colombia Bar.

Kelly Grace

Kelly is an Associate at Oscar L. Garza and Associates, P.C. She focuses her practice on state and federal motor fuel excise taxes and tax system implementation and optimization. Her tax practice covers all aspects of compliance with federal and state excise taxes including federal and state registrations, federal and state motor fuel excise taxes and environmental fees, federal biofuel tax credits and taxes and fees due on importation, including oil spill fees

Kelly was formally a Senior Tax Analyst at Sunoco, Inc. (R&M) where she managed indirect tax audits, assisted with implementing indirect tax reporting software, and filed state motor fuel tax returns as well as sales and use tax returns. During her time at Sunoco she directed the implementation of Avalara and she assisted in the tax configuration of Sabrix and SAP. Additionally, Kelly served as a liaison between Sunoco and E&Y to ensure the outsourced sales and use tax returns met all government requirements and were filed in a timely manner. Prior to working in Sunoco’s tax department, she was part of Sunoco’s financial associate program. As a financial associate, Kelly worked in Sunoco’s corporate auditing department and in the derivatives group.

Kelly graduated with honors in Accounting and Economics from the University of Delaware. She received her JD from Temple University Beasley School of Law. She is a Certified Public Accountant and a member of the Pennsylvania Bar.