About Spiegel Rosenthal Professional Corporation

Spiegel Rosenthal Professional Corporation is a firm of barristers and solicitors built around one specific practice: business, corporate, commercial and health law for dentists. The firm carries the name of Barry Spiegel, Q.C. (1936 to 2014), and its senior lawyer today is David E. Rosenthal.

Rosenthal's practice is devoted almost entirely to dentists and dental practices across Ontario. The firm advises on the purchase and sale of dental practices, on practice and corporate reorganizations, and on the professional corporations, technical service corporations and hygiene service corporations that dentists use to structure their businesses. It also drafts and negotiates the agreements that keep a dental office running day to day, including associate agreements, partnership and cost sharing arrangements, technical and hygiene service agreements, and shareholder agreements.

Rosenthal is also a guest lecturer at the Faculty of Dentistry at the University of Toronto and at the Schulich School of Medicine & Dentistry at Western University, and speaks regularly to dental associations and their professional advisors around the province. Rosenthal writes a regular column on legal issues for Ontario dentists in The Professional Advisory for Dental Professionals and contributed the legal chapter to the Ontario Dental Association's Dentist's Tax & Financial Guide.

Milestones & recognition

  • The firm carries the name of Barry Spiegel, Q.C. (1936 to 2014).

In the community

  • David E. Rosenthal is a guest lecturer at the Faculty of Dentistry, University of Toronto, and at the Schulich School of Medicine & Dentistry, Western University.
  • Rosenthal has given seminars to dental groups and their advisors, including the Ontario Dental Association, the Royal College of Dental Surgeons of Ontario, the Toronto Academy of Dentistry, Alpha Omega Toronto, the Brant County Dental Society, the Thunder Bay Dental Association and the Waterloo Wellington Dental Society.
  • Rosenthal is a regular columnist for The Professional Advisory for Dental Professionals, writing on legal matters for Ontario dentists.
  • Rosenthal is the contributing author on legal matters for the Ontario Dental Association's Dentist's Tax & Financial Guide, prepared for ODA members.

Good to know

A person using a wheelchairWheelchair accessibleA calendar with a checkmark beside a clockBy appointment

The neighbourhood

Spiegel Rosenthal's clients aren't a local walk-in crowd. The firm's own account of its practice describes advising dentists throughout Ontario, and its list of speaking engagements stretches from Brant County and Waterloo Wellington to Thunder Bay. For a firm built around one profession rather than one location, that province-wide reach is the more meaningful measure of where it works.

Frequently asked questions

Does Spiegel Rosenthal handle general legal matters, or just dental law?
The firm's practice is focused specifically on business, corporate, commercial and health law for dentists and dental practices, not general legal work.
Can Spiegel Rosenthal help me buy or sell a dental practice in Ontario?
Yes. Purchase and sale of dental practices is one of the firm's core areas of work.
Does the firm set up professional corporations for dentists?
Yes. The firm advises on dentistry professional corporations, technical service corporations and hygiene service corporations, along with related reorganizations.
Can Spiegel Rosenthal draft an associate agreement or partnership agreement for my practice?
Yes. The firm drafts and negotiates associate agreements, partnership and cost sharing arrangements, technical and hygiene service agreements, and shareholder agreements for dental practices.
Is Spiegel Rosenthal only able to work with dentists in one city?
No. The firm advises dentists throughout Ontario, and its lawyer has spoken to dental groups from Thunder Bay to Brant County.
Whose name does the firm carry?
The firm carries the name of Barry Spiegel, Q.C. (1936 to 2014). Its senior lawyer today is David E. Rosenthal.

Where to find them

2410-401 Bay Street, Toronto, Ontario M5H 2Y4 · 416-865-9677

Similar firms in City of Toronto

Bridging Legal Solutions (BLS) is a business law firm based in Toronto that serves startups, established businesses, and healthcare organizations across Ontario, New Brunswick, and the rest of Canada. It operates as a…

Business & Corporate LawBusiness & Corporate LawEmployment & Labour LawEmployment & Labour LawIntellectual PropertyIntellectual PropertyHealth LawHealth Law

Jasmine Mary Ghosn is a sole practitioner licensed in Ontario and Nova Scotia, representing regulated health care professionals since 2000. Based between Toronto and Halifax, she handles health law and professional di…

Health LawHealth LawAdministrative & Regulatory LawAdministrative & Regulatory LawCivil Litigation & Dispute ResolutionCivil Litigation & Dispute ResolutionBusiness & Corporate LawBusiness & Corporate Law

Blaney McMurtry LLP is a full-service Toronto law firm ranked among the top regional law firms in Canada, with lawyers practising across areas including commercial litigation, real estate, employment, insurance, const…

Business & Corporate LawBusiness & Corporate LawCivil Litigation & Dispute ResolutionCivil Litigation & Dispute ResolutionReal Estate LawReal Estate LawEmployment & Labour LawEmployment & Labour Law

Listing compiled from the firm’s public website in August 2026. Verify licence status in the Law Society of Ontario directory ↗