Ontario, CA downtown - hub of construction industry

Ontario Construction & Business Litigation Firm

Ghassemian Law Group is a boutique law firm with a focus on business and construction litigation. Our ability to balance a small firm’s attentive touch and a big firm’s expansive knowledge enables us to conquer even incredibly complicated construction cases.


With a population of 177,963, Ontario is located just east of Los Angeles. Ontario International Airport, the 15th busiest airport in the country by mass of freight, is located in the city. Agriculture fueled the early economy, and Ontario also has a legacy of two centuries of Hispanic residents living in the area. Ontario is home to a handful of upscale neighborhoods, including Downtown Ontario, Creekside, and New Haven. This area is ideal for anyone looking for a diverse yet historically-rooted city.


Whether you are an architect, engineer, CEO, construction business owner, luxury homeowner, or residential project developer, we are confident that we can handle your case with ease and confidence. Technical construction cases can be complicated, but our attorneys are highly capable of converting industry terms into words that are digestible by judges and juries. If you choose Ghassemian Law Group, you can expect a deep knowledge of the following:

As an individual taking legal action to receive the pay you deserve or a construction company pushing for a fair outcome, we are ready to fight for you here at Ghassemian Law Group. Not only assisting you in court, we also create opportunities to help improve your contacts and business structure. Let us help you get back to what you love, no strings attached.

If you are a resident of Ontario or the surrounding area, Ghassemian Law Group would love to assist you in protecting your business, construction company, or individual career. Our unique blend of small-firm attention to detail and big-firm knowledge are just what


Ghassemian Law provided thoroughly constructed and effective legal strategies for successful outcomes in the complex world of construction law for our small company. Core competence, due diligence, and a commitment to client needs are strengths that inspire confidence and keep producing results when it counts most.

Peter Greenberger

Pacwest Construction and Development Inc

Mahyar and her team possess a wealth of construction and business law expertise. Expertise to both guide a client away from litigation and, if not possible, to skillfully represent them in court.

Thierry Montoya

AlvaradoSmith APC

Mahyar Ghassemian and her firm are the best construction dispute litigators and negotiators in the industry. Mahyar is an expert in this area. Her firms knows the law and are very tenacious in obtaining the best results for their clients. I have been involved in very lengthy litigation as co-counsel in a very big case and jury trial. Mahyar is one of the hardest working and most effective advocates I have ever had the privilege of working with.

Paul Hoffman

Hoffman Legal Corporation

Small Firm Value – Large Firm Expertise