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California contractor license
C N K Cornerstone Inc
C N K Cornerstone Inc of Chino Hills holds California license 854438 (C27 Landscaping). The CSLB file dated Oct 31, 2026 lists it as active.1 It expires Feb 28, 2027.
Active
C N K Cornerstone Inc, Chino Hills
- License
- 854438
- Class
- C27 Landscaping
- Expires
- Feb 28, 2027
- Workers' comp
- Insured to Jun 1, 2027
CSLB file dated Oct 31, 2026
From the CSLB file dated Oct 31, 2026. Not a consumer report; check the board before you hire.
Has the board taken action on this license?
None in the CSLB file dated Oct 31, 2026. Confirm with the board: CSLB license check
What bond, insurance and workers' comp are on file?
- Bond
- None on file
- Liability insurance
- Not in the CSLB fileCheck with the board
- Workers' comp
- InsuredState Compensation Insurance Fund, from Jun 1, 2013, to Jun 1, 2027
Who is on this license?
- Responsible managing officer
- Sun M. KwonSince Feb 11, 2005
- CEO and president
- Won K. ChungSince Feb 11, 2005
What work does this license cover?
Issued Feb 11, 2005.
- C27 Landscaping
Which other Chino Hills businesses hold C27 Landscaping?
- Ujihara Landscape IncLicensed since 1983
- GQ Landscape Care IncLicensed since 2004
- Kirton's Landscape Maintenance Inc A California CorporationLicensed since 2006
- Green Climate Landscape Maintenance IncLicensed since 2011
- Mantis Turf & LandscapeLicensed since 2018
What should you check before hiring?
What to ask before you hire
- Get the license number in writing. The name on the license should match the name on your contract and invoice.
- Check the class covers the job. A license for one trade doesn't cover another. California license classes
- Ask for a certificate of insurance sent to you by the insurance agent, not handed over by the contractor. How to read a COI
- Ask who will be on site. If a crew works on your property, ask for proof of workers' comp. An exemption on file means the contractor told the CSLB it has no employees.
- Put it in a written contract: license number, price, start date and payment schedule. Check the license again on the day you sign.
If the license is lapsed
- Don't sign or pay a deposit until the CSLB shows the license active again.
- Ask the contractor why. For a bond or insurance lapse, ask for proof that the new bond or policy was filed with the CSLB, then check again.
- If work has started, hold further payments, keep the contract, receipts and photos, and file a complaint with Contractors State License Board (CSLB).
- Check another contractor. California license lookup
Sources
- CSLB License Master (cslb.ca.gov, Oct 31, 2026)
- Contractors State License Board (CSLB)