Tax problems create turbulence and uncertainty. We provide solutions and tranquility.

We focus exclusively on assisting individuals and businesses worldwide in resolving their US tax problems and tax disputes.

The Law Offices of Gregory S. Martinelli is a boutique tax controversy law firm focused on assisting individuals, businesses, and business owners in resolving their US tax problems and tax disputes.  The firm routinely represents clients before the Internal Revenue Service (IRS) and state tax authorities. The firm also counsels clients in planning transactions so they can avoid future tax controversies. In addition, the firm counsels accounting firms and tax professionals on a range of federal (and state) tax practice and procedure issues.

Why Choose Gregory S. Martinelli?

Greg counsels businesses and individuals worldwide on ways to resolve or mitigate their US tax problems and tax disputes. He routinely represents clients before the Internal Revenue Service in examinations, penalty disputes, collection matters, and administrative appeals. Greg also represents clients in state tax disputes, including personal income tax audits and sales/use tax audits. Working with the IRS National Office, Greg has secured favorable private letter rulings and 9100 rulings for his clients as well as negotiated favorable closing agreements and pre-filing agreements. Greg counsels clients with foreign assets/activities as well as foreign clients with US activities on US tax compliance and tax reporting requirements, including issues relating to undeclared offshore accounts. Greg serves as tax controversy counsel to accounting firms throughout the United State and advises the firms on a variety of international, federal, and state practice/procedure and substantive tax matters.

For a consultation please call us at 610-520-1900 or contact us online.

Representative Matters

Client Profile

Global Insurance Company


IRS required the company to implement a federal reportable transaction/material advisor disclosure program for US operations.


Designed/developed a program and, working with company’s tax group and information technology group, was responsible for overseeing the program’s implementation.

Client Profile

UK-Based Consumer Products Company


Company failed to file numerous international information returns for a particular tax year; the IRS assessed a late-filing penalty in excess of $800,000.


Succeeded in having the $800,000 penalty abated in its entirety.

Client Profile

Privately-Held Domestic Contract Staffing Services Company


Company’s former chief financial officer failed to make federal withholding tax payments resulting in an approximately $1 million tax liability.


Negotiated offer-in-compromise settling company’s liability for approximately 20 percent of the total outstanding liability.

Latest Speaking Engagements

  • Advising the Individual Taxpayer with Delinquent International Information Returns: Some Key Considerations, American Academy of Attorney-CPAs (Greater Philadelphia/Delaware Valley Chapter), Virtual Presentation, February 16, 2022.

  • Circular 230: The Basics (and More), Society of Financial Service Professionals (Greater Philadelphia Chapter), Wayne, Pennsylvania, May 9, 2019.

  • Villanova University Graduate Tax Program, Adjunct Professor (live and on-line course instruction), 2016 – Present.

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