Peter Rosenberg
Partner
Peter is President and the Principal Member of Peter Rosenberg & Partners LLC. He assists families and other private clients concerning their personal and investment connection to the United States. Peter is a practicing attorney, focusing on the U.S and international tax planning, compliance and administration.
Peter is a 1996 graduate of Villanova University School of Law (LL.M. Tax), a 1993 graduate of Temple University School of Law and a graduate of the University of Pennsylvania. Peter is admitted to practice in New York, Pennsylvania and in the United States District Court for the Eastern District of Pennsylvania.
Prior to establishing Peter Rosenberg & Partners LLC and Stonehage Fleming US LLC, Peter was a partner in the Philadelphia law firms Cozen O’Connor and Duane Morris, LLP.
He is a member of several professional organizations including the Society of Trust and Estate Practitioners (STEP) and several bar associations.
Jeffrey A. Hollowniczky
Director
Jeffrey is a Director and US Head of Tax Compliance and Client Reporting. He assists families and other private clients in U.S. tax planning and related compliance issues with an emphasis on cross border taxation and compliance. He assists his attorney colleagues in the tax and financial planning portion of the advice they provide. He also oversees the management of various client investment structures.
Jeffrey joined the Group in 2011 after several years working for a U.S. based private multi-client Family Office. Prior to this he spent several years in public accounting serving private clients. He is a Certified Public Accountant and holds a B.S. in Accounting from Rutgers University. He is a Certified Management Accountant (CMA) and a member of both the American Institute of Certified Public Accountants (AICPA) of Society of Trust and Estate Practitioners (STEP).
Rosalind Karlin
Senior Associate
Rosalind is a Senior Associate Attorney at Stonehage Fleming Law US. She assists individuals and families regarding United States tax planning, intergenerational wealth transfers, estate and trust administration, and charitable giving. Rosalind has been nominated as a court appointed Trustee and Guardian throughout Pennsylvania.
Prior to joining Stonehage Fleming Law US in 2025, Rosalind practiced law at the Pennsylvania Office of Attorney General, where she led the Eastern Region’s Charitable Trusts and Organizations department, and as a solo practitioner specializing in estate and trust administration and fiduciary services.
She holds a Master of Laws in taxation and a Juris Doctor from Temple University’s Beasley School of Law and a Bachelor of Arts. from the University of Pennsylvania. Rosalind is admitted to practice law in Pennsylvania and the United States Eastern District Court of Pennsylvania.
Aaron LeClair
Associate Attorney
Aaron is an Associate at Stonehage Fleming Law US. He works closely with individuals and families to develop thoughtful U.S. tax strategies, guide intergenerational wealth transfers and support the smooth administration of estates and trusts.
Prior to joining Stonehage Fleming Law US in 2025, Aaron practiced at Stradley Ronon Stevens & Young, LLP, where he gained extensive experience in estate planning and trust administration. He earned his Master of Laws in Taxation from Temple University Beasley School of Law and his Juris Doctor from Washington and Lee University School of Law.
Aaron is admitted to practice law in Pennsylvania and New Jersey.
Angela Villari
Legal Administrative Assistant
Angela provides administrative assistance to attorneys in the US Legal Department.
She joined the Group in 2023 as member of the legal team in the Philadelphia office after holding legal assistant positions for over 20 years.
Maureen Hayward
Legal Assistant
Maureen provides legal administrative assistance to the Head of US Legal department.
Maureen joined the Group in 2018 as member of the legal team in the Philadelphia office after holding similar legal administrative positions over the last 35 years.