Every new California business filing, every dayO'Brien Law
Sarah K. O'Brien, Registered Agent
The LLC operates as O'Brien Law, P.C., a litigation-focused law firm based in Petaluma, CA. The firm emphasizes customer service and experience in construction law. The principal address is not listed in the filing, but the website provides a specific address and phone numbers.
Filed March 17, 2026 · Costa Mesa, CA · Orange County
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California Secretary of State (bizfile Online) · Entity B20260132113 · Retrieved May 14, 2026
About O'Brien Law
SARAH K. O'BRIEN LAW, A PROFESSIONAL CORPORATION filed in California on March 17, 2026, as a litigation law firm in Costa Mesa. Owner Sarah K. O'Brien filed personally as the registered agent. Its domain was registered in 2016, over ten years before filing. We estimate annual revenue between $1 million and $10 million with 6-25 employees. The firm operates from a brick-and-mortar location. No annual report or EIN on file yet.
- Domain registered over ten years before the company filing.
- Owner filed personally as the registered agent.
- We estimate revenue of $1M-$10M and 6-25 employees.
- Brick-and-mortar footprint indicates a physical office.
- No annual report or EIN on file yet.
Compiled from the state record, the company's public web presence, and our own research; revenue, employee, and footprint figures are estimates, not verified financials. Updated August 23, 2026.
One of 51 new businesses registered in Costa Mesa in March 2026, one of 2 law firm businesses.
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Filing Details
Verified Business Profile
Contact Information
Verified Website Profile
We matched this business to its website and pulled the domain's registration (WHOIS) record. Domain age is one of the strongest signals that a filing is a truly new business and not a re-filing or paperwork change.
Frequently Asked Questions
When was O'Brien Law registered?
O'Brien Law was registered as Corp on March 17, 2026 in California.
Where is O'Brien Law located?
O'Brien Law is based in Costa Mesa, CA, 92626, in Orange County.
What type of business is O'Brien Law?
O'Brien Law is classified as a law firm business (litigation).
Does O'Brien Law have an EIN on file?
No EIN was found on file for O'Brien Law at the time of registration.
Who Sells to This Business
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