Staff Profiles


David Simpson is a certified public accountant who has specialized in financial and tax planning for more than 35 years – always in the public accounting sector. David’s certifications and affiliations are numerous; beginning with his Bachelor of Science – Accounting emphasis from the University of Southern California, he has been a Certified Public Accountant in the state of California since 1983, a member of the American Institute of Certified Public Accountants (AICPA) and California Society of Certified Public accountants.

Owning his own Certified Public Accounting firm since 1986 was the natural progression for David after having spent six years with the “Big Eight” firm of Touche Ross (now known as Deloitte.) in both the auditing and tax departments. During those years David pursued a graduate degree Masters in Business Taxation from the University of Southern California which was completed in 1987.

Since owning his own firm, David has enjoyed the challenge of the field of taxation and directed the firm to specialize in business and individual tax planning and preparation. Whereas the firm also provides services in the areas of accounting and accounting software consulting the main emphasis has been in tax planning and preparation.

Outside of the office, David has pursued an interest in ice hockey into actually playing “fun” level hockey, coaching his daughter’s sports teams, traveling as much as time will permit and spending time with his family.


SHAY LEIMBACH | Accounting Manager



ASHLEY HART | Accounting Supervisor

While earning her B.A. in Business Accounting from California State University, Fullerton, Ashley began working at Simpson & Co at the age of 19. Since graduating in 2009 she has immersed herself in her accounting duties increasing her time spent onsite with clients. While Ashley spends most of her time providing services for her business clients she also has a passion for individual taxation and assists in preparing tax returns when she can.

Ashley’s other interests include traveling with her husband (of course not during tax season), culinary arts, dance, video editing, and spending time with her two dogs Wilbur and Harley.


YSABEL GARCIA | Administrative Assistant

Ysabel joined the Simpson & Co staff in June 2015 as our administrative assistant. She is currently attending California State University, Fullerton, and pursuing a degree in Business Administration with a concentration in accounting. Some of her daily duties include answering phones, scheduling appointments, and mailing returns. She’s also in charge of the company website, pretty cool right?

In her free time Ysabel enjoys traveling, taking photos, going to concerts, and binge watching TV shows. Her favorite TV show is HBO’s Game of Thrones.