Doble Engineering Company
Doing business as Doble CO
At a glance
Employees100-499
In business sinceNot reported
Industry
HeadquartersMarlborough, MA
US patents31
SAM.gov UEIPNL1LJQ5G8H6
CAGE code94856
Incorporated inMA
Parent companyEsco Technologies INC.
LEI549300AS7HV2AQPLV521
Brands
This company sells these brands.
- condition monitoring
- electrical test instruments
- high power test systems
- tests
- circuit breakers
- transformers
- cables
- overhead lines
- rotating machines
- insulating materials
- DC HIPOT/Insulation
Named on the company’s own website, read JUL 29, 2026
CareersCareers page — seen SEP 8, 2026
Supplier designations
For Profit OrganizationManufacturer of Goods
Self-certified by the company in its SAM.gov registration
Patents
31 US patents granted 1977–2025, 8 of them in the five years to SEP 2025, including 2 design patents.
Measurement 16Electrical machinery, apparatus, energy 5Basic communication processes 3Digital communication 2Computer technology 2
- Relay and metering test instrumentUS 12,210,441 · granted JAN 28, 2025
- Optimizing transformer exciting current and loss test results by dynamically managing core magnetic stateUS 12,094,651 · granted SEP 17, 2024
- Configurable test instrument for power equipmentUS D1026694 · granted MAY 14, 2024
- Relay and metering test instrumentUS 11,886,324 · granted JAN 30, 2024
- Configurable test instrument for power equipmentUS 11,614,465 · granted MAR 28, 2023
Newest 5 shown · Granted to Doble Engineering Company · PatentsView (USPTO), data through SEP 30, 2025 · CC BY 4.0
Their plants
8 FACILITIES| Facility | City | State | Employees | Status |
|---|---|---|---|---|
| Doble Engineering Company (Ontario, CA) | Ontario | CA | 20–99 | LIKELY ACTIVE |
| Doble Engineering Company (Indianapolis, IN) | Indianapolis | IN | 1–19 | LIKELY ACTIVE |
| Doble Engineering Company | Marlborough | MA | 100–499 | ACTIVE |
| Doble Engineering Company | Watertown | MA | — | UNVERIFIED |
| Doble Engineering Company (Accident, MD) | Accident | MD | 100–499 | LIKELY ACTIVE |
| Doble Engineering Company (Morrisville, NC) | Morrisville | NC | 20–99 | LIKELY ACTIVE |
| Doble Engineering Company (Tulsa, OK) | Tulsa | OK | 1–19 | LIKELY ACTIVE |
| Doble Engineering Company (Houston, TX) | Houston | TX | 1–19 | LIKELY ACTIVE |
Compiled from federal records — EPA, OSHA, SAM.gov and the U.S. Census — and from the company’s own website. Federal source data is public domain. Each plant’s page names the source of every field.