Company lists · Data refreshed November 2026

Top 25 Undercover investigation services worldwide

RevenueBase identified 2,217 company matches for undercover investigation services worldwide as of November 2026 and tracks 11,531 professional contacts across them, including 2,563 with verified work emails. The United States is the largest market and London the largest hub.

This list covers company matches for undercover investigation services worldwide, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. Data refreshed November 6, 2026. Country and city lists for undercover investigation services follow the table.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase SmartSearch, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list RevenueBase SmartSearch · Exact Recorded Nov 6, 2026 How this list was built
2,217Companies
11,531Contacts tracked
2,563Verified emails
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The 25 largest undercover investigation services worldwide

Ranked by team size
Top 25 of 2,217 company matches for undercover investigation services worldwide, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Nov 6, 2026. The RevenueBase SmartSearch column shows Exact match membership in this saved search. Click a contact count to view that company's people. Totals use company locations recorded by RevenueBase; the displayed preview is a smaller selection.
#CompanyRevenueBase SmartSearchHeadquartersEmployeesContacts
1Exact matchAtlanta, GA, United StatesHQ recorded Nov 6, 2026501-1,000378 contacts →

Exact match

“A full-service firm with the proven capabilities to manage all facets of your company’s security requirements, Norred & Associates, Inc.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
2Exact matchJacksonville, FL, United StatesHQ recorded Nov 6, 2026501-1,000377 contacts →

Exact match

“CoventBridge Group is the leading worldwide full service investigation solutions company providing: Surveillance, SIU and Compliance, Claims Investigation, Counter-Fraud Programs…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
3Exact matchNew York, NY, United StatesHQ recorded Nov 6, 2026201-500367 contacts →

Exact match

“Vcheck is a global investigations firm that helps institutions protect their investments by providing intelligence on individuals and entities.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
4Exact matchDavis, CA, United StatesHQ recorded Nov 6, 2026201-500359 contacts →

Exact match

“DigiStream Investigations is a full-service private investigation firm specializing in insurance defense and legal support services.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
5Exact matchKannapolis, WA, United StatesHQ recorded Nov 6, 2026201-500225 contacts →

Exact match

“Advantage Investigations is a nationwide leader in the industry for investigative services.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
6Exact matchIrvine, CA, United StatesHQ recorded Nov 6, 2026201-500222 contacts →

Exact match

“Frasco has hundreds of investigators and regional offices located throughout the country.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
7Exact matchNorth Haven, CT, United StatesHQ recorded Nov 6, 2026501-1,000138 contacts →

Exact match

“Knowledge is power" Whether you are an insurance company, TPA, insurance defense law firm, risk manager, private law firm, or corporation / business owner, we at Lemieux &…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
8Exact matchNew York, NY, United StatesHQ recorded Nov 6, 202651-200130 contacts →

Exact match

“Beau Dietl & Associates is a premier private investigation firm based in New York City with offices in New Jersey, Florida, and California.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
9Exact matchNew York, NY, United StatesHQ recorded Nov 6, 202651-200121 contacts →

Exact match

Recorded description not available.

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
10Exact matchUnited StatesHQ recorded Nov 6, 2026201-500104 contacts →

Exact match

“Why Becker & Company?”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
11Exact matchTroy, MI, United StatesHQ recorded Nov 6, 2026201-500101 contacts →

Exact match

“The Robison Group is an agency of professional investigators and support teams offering surveillance, SIU claims, business risk mitigation and comprehensive desktop investigation…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
12Exact matchHuntington Beach, CA, United StatesHQ recorded Nov 6, 202651-20094 contacts →

Exact match

“Horsemen Investigations is a full service investigation company, specializing in investigating insurance fraud and in minimizing risk exposure.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
13Exact matchNew York, FL, United StatesHQ recorded Nov 6, 2026201-50075 contacts →

Exact match

“Integrated Security Services, Inc.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
14Exact matchMonaca, PA, United StatesHQ recorded Nov 6, 2026201-50073 contacts →

Exact match

“CSI is a full-service investigative firm that delivers key facts to give our clients an actionable advantage in a wide range of situations.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
15Exact matchWashington, DC, United StatesHQ recorded Nov 6, 202611-5070 contacts →

Exact match

“Investigative Group International (IGI) is the premier investigative firm conducting independent, high-touch investigations worldwide.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
16Exact matchToronto, ON, CanadaHQ recorded Nov 6, 202651-20068 contacts →

Exact match

Recorded description not available.

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
17Exact matchWoburn, MA, United StatesHQ recorded Nov 6, 2026201-50066 contacts →

Exact match

“Claims Bureau USA has been providing Insurers, TPA's and their defense counsel with quality, in-depth investigative services since 1956.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
18Exact matchCarlton, AustraliaHQ recorded Nov 6, 202651-20066 contacts →

Exact match

“For decades, LKA Group has provided the highest level of service to all clients, from small business to multinational corporations and governments.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
19Exact matchSacramento, CA, United StatesHQ recorded Nov 6, 202651-20065 contacts →

Exact match

“Today’s professionals rely on investigative firms to help manage risk by detecting and preempting problem situations.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
20Exact matchAlpharetta, NJ, United StatesHQ recorded Nov 6, 202651-20065 contacts →

Exact match

“Founded in 1978, Smith & Carson is a trusted and highly experienced investigative research firm that partners with the world's leading organizations to handle complex…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
21Exact matchRome, ItalyHQ recorded Nov 6, 2026201-50061 contacts →

Exact match

“Global Investigation Service operates on the whole national territory in accordance with the Law 134 T.U.L.P.S.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
22Exact matchMontréal-nord, CanadaHQ recorded Nov 6, 202651-20055 contacts →

Exact match

“SIRCO offers efficient investigative methods to counter: Theft, Fraud, Collusion with Suppliers, Drug Trafficking, Threats, Trademarks Piracy, Labour Disputes, Harassment…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
23Exact matchBolton, United KingdomHQ recorded Nov 6, 202651-20053 contacts →

Exact match

“ExamWorks Investigation Services is a leading claims investigation company providing the insurance, banking, retail and other sectors with a range of innovative and cost effective…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
24Exact matchDurban, South AfricaHQ recorded Nov 6, 202611-5052 contacts →

Exact match

“Justicia Investigations provides a range of professional investigative services including: Forensic investigations | Facts and truth discovery and verification (credential…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
25Exact matchNew Bedford, NY, United StatesHQ recorded Nov 6, 202611-5050 contacts →

Exact match

“Established in 1981, Data Quest, Ltd.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase

Showing 25 of 2,217 undercover investigation services worldwide

See the full list, filter by size, metro and specialty, and access 2,563 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Undercover investigation services worldwide at a glance

As of Nov 6, 2026
22.2%Verified-email coverage
5.2Average contacts per company
1-10Median size (employees)
1.8%Largest-city concentration · London
Nov 6, 2026Page data refreshed

Companies by employee count

1-10
1,593
11-50
432
51-200
123
201-500
34
501-1,000
8
1,001-5,000
1
10001+
2

Email recency is reported on each country list linked below.

How this list was built

The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.

Source
The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase SmartSearch, the natural-language company search available to every RevenueBase user.
Coverage
Every country. Country and city lists for undercover investigation services are linked below.
What qualifies
Company records worldwide whose business descriptions match “undercover investigation services” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
RevenueBase SmartSearch
Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
Public preview
The public preview omits records without a verified work email. Dataset totals and geographic summaries describe the full matched records before these preview filters.
Match quality
RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
Ranking
Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification
Every displayed company carries at least one verified work email. RevenueBase tracks 2,563 professional contacts with verified work emails across the full matched dataset. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh
This page's figures were pulled from the company graph on November 6, 2026. Lists refresh periodically as the graph is re-checked.
Record context
Company records and descriptions can change. Check the company's website for its current services and locations.

Undercover investigation services by location

4 lists · largest first

Every Undercover investigation services list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.

Countries

Frequently asked

What is RevenueBase SmartSearch?

RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “undercover investigation services”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many undercover investigation services are there worldwide?

RevenueBase identified 2,217 company matches for undercover investigation services worldwide as of November 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.

What is the largest company on this list?

Norred & Associates, INC tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which country has the most undercover investigation services?

The United States leads with 1,104 companies, followed by the United Kingdom (128) and Canada (76). Every undercover investigation services list by country and city is linked on this page.

Which city has the most undercover investigation services?

London leads with 41 company records, followed by New York (22) and Rome (20).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 2,563 professional contacts with verified work emails tracked across these 2,217 companies; direct dials are available where recorded.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on November 6, 2026.

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About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase SmartSearch, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.