Semaphore Corporation
Specialty 09 · Mercer Island, WA · License #SEMAPC*934QW
Registration expired per WA L&I as of Jan 30, 2026.
How confident can you be in Semaphore Corporation?
Are they licensed, bonded, and insured?
Registration expired per WA L&I as of Jan 30, 2026.
Are they who they say they are?
Not yet verified — this listing hasn't been claimed. Own this business? Claim it free.
Do other pros stand behind them?
No endorsements yet from licensed contractors.
Do they have jobs on record?
Not yet measured — performance data comes from real jobs, not reviews.
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License facts
Principals on record since 2007.
- License type
- ELECTRICAL CONTRACTOR
- Effective date
- Jan 30, 2008
- Expiration date
- Jan 30, 2026
- Suspend date
- Aug 3, 2025
- UBI
- 601675561
- Business type
- Corporation
- Phone
- (206) 905-5000
- Location
- Mercer Island, WA 98040
Source: WA L&I contractor registration — checked Aug 17, 2026. Applies to every row above.
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Claim this free listingBond & insurance on file
What the bond and insurance requirements mean for homeowners
Washington requires specialty contractors to file a $15,000 surety bond with the Department of Labor & Industries as a condition of registration ($30,000 for general contractors).
The bond is a limited fund a homeowner (or subcontractor or supplier) can make a claim against, through the courts, if a registered contractor fails to meet its obligations on a job. Contractors must also keep general liability insurance on file — at least $50,000 in property damage and $200,000 in public liability coverage, or a $250,000 combined single limit — which covers damage the contractor causes, not workmanship disputes. The rows above are the bond and insurance filings L&I publishes for this registration; whether a specific filing applies to a specific project depends on its dates and terms.
Principals
| Name | Start date |
|---|---|
| Garth Brown | Nov 16, 2007 |
| Roy Simperman | Nov 16, 2007 |
| Roy Simperman | Nov 16, 2007 |
What is a Specialty 09 contractor licensed to do in Washington?
Specialty 09 is a classification code the state registry uses for certain specialty contractors; the registry does not publish a more specific trade description for it. Check a listing's own license facts and the contractor's stated services for what a particular business does. The registration requires a $15,000 surety bond and general liability insurance on file with WA L&I.
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Built from Washington State L&I public records, updated Aug 17, 2026. Subser doesn't do star ratings or reviews — just verified records.