Company lists · Data refreshed September 2026

Top 25 Investigative research firms based in the United States

RevenueBase identified 1,750 company matches for investigative research firms associated with the United States as of September 2026 and tracks 15,055 professional contacts across them, including 4,559 with verified work emails. New York is the largest hub.

This list covers company matches for investigative research firms associated with the United States, 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 September 20, 2026.

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 Sep 20, 2026 How this list was built
1,750Companies
15,055Contacts tracked
4,559Verified emails
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The 25 largest investigative research firms based in the United States

Ranked by team size
Top 25 of 1,750 company matches for investigative research firms based in the United States, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Sep 20, 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 matchHerndon, VA, United StatesHQ recorded Sep 20, 20261,001-5,000677 contacts →

Exact match

“OMNIPLEX World Services Corporation is a leader and innovator in delivering professional background investigations, intelligence support, and physical security services to…”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
2Exact matchGrand Rapids, MI, United StatesHQ recorded Sep 20, 20261,001-5,000572 contacts →

Exact match

“DK Security is unique in that it offers a single company for a wide ranging availability of security and investigative services.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
3Exact matchJacksonville, FL, United StatesHQ recorded Sep 20, 2026501-1,000518 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 · Sep 20, 2026 · View company records in RevenueBase
4Exact matchNew York, NY, United StatesHQ recorded Sep 20, 2026201-500336 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 · Sep 20, 2026 · View company records in RevenueBase
5Exact matchDavis, CA, United StatesHQ recorded Sep 20, 2026201-500327 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 · Sep 20, 2026 · View company records in RevenueBase
6Exact matchBroussard, LA, United StatesHQ recorded Sep 20, 2026501-1,000292 contacts →

Exact match

“HUB Enterprises is a national insurance defense investigative firm.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
7Exact matchNew York, NY, United StatesHQ recorded Sep 20, 2026201-500268 contacts →

Exact match

“We stand at the forefront of leadership, insight, and guidance in a world marked by complexity and uncertainty.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
8Exact matchIrvine, CA, United StatesHQ recorded Sep 20, 2026201-500214 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
9Exact matchKannapolis, NC, United StatesHQ recorded Sep 20, 2026201-500214 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
10Exact matchCharlotte, NC, United StatesHQ recorded Sep 20, 20261,001-5,000203 contacts →

Exact match

“Alpine Intel is dedicated to innovation across the property, auto, liability, and workers' comp insurance fields-helping our customers reach peak performance throughout the policy…”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
11Exact matchWashington, DC, United StatesHQ recorded Sep 20, 202651-200179 contacts →

Exact match

“Quadrant Strategies helps the world’s most prominent companies navigate their most important brand, reputation, and product challenges.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
12Exact matchSpring, TX, United StatesHQ recorded Sep 20, 202651-200152 contacts →

Exact match

“Promark Research Corporation is headquartered in Spring, Texas, a few miles North of Houston.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
13Exact matchCleveland, OH, United StatesHQ recorded Sep 20, 202651-200151 contacts →

Exact match

“Cleveland Research Company is an independent research firm headquartered in Cleveland, Ohio.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
14Exact matchFort Worth, TX, United StatesHQ recorded Sep 20, 202651-200146 contacts →

Exact match

“A federally qualified Small Business, IDS offers end to end investigative solutions tailored to meet the specific needs of our clients.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
15Exact matchWashington, DC, United StatesHQ recorded Sep 20, 202651-200142 contacts →

Exact match

“PSA is a global due diligence and investigations firm headquartered in Washington, DC.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
16Exact matchSan Diego, CA, United StatesHQ recorded Sep 20, 202611-50141 contacts →

Exact match

“TrendSource helps businesses document and measure compliance across employment, consumer reporting, government, finance, health care, and retail.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
17Exact matchNew York, NY, United StatesHQ recorded Sep 20, 202651-200129 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 · Sep 20, 2026 · View company records in RevenueBase
18Exact matchNorth Haven, CT, United StatesHQ recorded Sep 20, 2026501-1,000119 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 · Sep 20, 2026 · View company records in RevenueBase
19Exact matchNew York, NY, United StatesHQ recorded Sep 20, 202651-200112 contacts →

Exact match

Recorded description not available.

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
20Exact matchLos Angeles, TX, United StatesHQ recorded Sep 20, 202651-200107 contacts →

Exact match

“Alias Intelligence is a leading background investigations and due diligence company delivering the information and insights our clients need to grow and navigate their businesses.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
21Exact matchTroy, MI, United StatesHQ recorded Sep 20, 2026201-500104 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 · Sep 20, 2026 · View company records in RevenueBase
22Exact matchWhite Plains, NY, United StatesHQ recorded Sep 20, 202651-20096 contacts →

Exact match

“Gryphon partners with clients across the globe to help them assess new opportunities and tackle their most complex problems often in challenging and opaque markets.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
23Exact matchUnited StatesHQ recorded Sep 20, 2026201-50094 contacts →

Exact match

“Why Becker & Company?”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
24Exact matchBethesda, MD, United StatesHQ recorded Sep 20, 202651-20093 contacts →

Exact match

“RosettiStarr provides cutting-edge intelligence, investigations, corporate risk and cyber security services to management teams, attorneys and investors worldwide.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase
25Exact matchCalabasas, CA, United StatesHQ recorded Sep 20, 202651-20085 contacts →

Exact match

“Davis Research is a privately held family business that has been executing projects for market research professionals since 1970.”

Recorded in the RevenueBase company graph · Sep 20, 2026 · View company records in RevenueBase

Showing 25 of 1,750 investigative research firms based in the United States

See the full list, filter by size, metro and specialty, and access 4,559 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Investigative research firms based in the United States at a glance

As of Sep 20, 2026
30.3%Verified-email coverage
8.6Average contacts per company
1-10Median size (employees)
3.6%Largest-city concentration · New York
Sep 20, 2026Page data refreshed

Companies by employee count

1-10
1,173
11-50
430
51-200
100
201-500
33
501-1,000
5
1,001-5,000
7

Email recency for this list is measured worldwide rather than for United States, so it is reported there. Company counts and contact totals on this page are exact for United States, over 1,750 companies.

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.
What qualifies
Company records associated with the United States whose business descriptions match “investigative research firms” 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. Where headquarters information is recorded, preview rows are also filtered to this page’s location. 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 4,559 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 September 20, 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.

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 “investigative research firms”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many investigative research firms are there based in the United States?

RevenueBase identified 1,750 company matches for investigative research firms associated with the United States as of September 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?

Omniplex World Services Corporation tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city has the most investigative research firms?

New York leads with 63 company records, followed by Washington (28) and Houston (25).

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 4,559 professional contacts with verified work emails tracked across these 1,750 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 September 20, 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.