Ko Jonathan, B General Building Contractor in Diamond Bar, CA
Ko Jonathan operating as a sole owner holds an active California contractor license (CSLB #939589), valid through Oct 31, 2027. First issued in 2009, the license has been on the CSLB roster for 17 years. It carries a single CSLB classification: B — General Building Contractor. Records show an active surety bond on file with Western Surety Company and an exempt workers' compensation status (no employees on payroll). The business is based in Diamond Bar, in Los Angeles County, California.
- License Number
- 939589
- Issued
- Oct 29, 2009
- Status
- CLEAR
- Expires
- Oct 31, 2027
- Entity
- Sole Owner
- Surety
- Western Surety Company
- Bond Number
- 67368052
- Effective
- Jun 8, 2025
- Status
- Active
- Coverage
- Exempt
- Carrier
- —
- Policy Number
- —
- Effective
- Sep 18, 2025
- Expires
- —
This contractor warrants a closer look before contracting:
- Workers' comp listed as exempt
An automated summary of public CSLB data, not a credit score, rating, or endorsement. How we determine this
Is Ko Jonathan licensed in California?
Yes. Ko Jonathan holds California Contractors State License Board license number 939589, which is active and in good standing. The license was first issued on October 29, 2009. It is valid through October 31, 2027.
What does Ko Jonathan specialize in?
Ko Jonathan is licensed for one CSLB classification: B General Building Contractor.
Where is Ko Jonathan headquartered?
Ko Jonathan is headquartered at 2028 Kiowa Crest Drive #2, Diamond Bar, CA 91765, in Los Angeles County, California.
Does Ko Jonathan have an active surety bond on file with CSLB?
Yes. Ko Jonathan has an active California contractor surety bond filed with Western Surety Company.
Does Ko Jonathan carry workers' compensation coverage?
Ko Jonathan reports an exempt workers' compensation status, meaning the business has no employees on payroll.
How do I verify Ko Jonathan's contractor license?
You can verify Ko Jonathan's license directly with the California Contractors State License Board at https://www.cslb.ca.gov/OnlineServices/CheckLicenseII/LicenseDetail.aspx?LicNum=939589.
- License issuedOct 29, 2009
- Bond activeJun 8, 2025
- WC coverage startsSep 18, 2025
- License expiresOct 31, 2027
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