Company lists · Data refreshed September 2026

Top 25 Investigative consulting firms based in New York, United States

Name: Investigative consulting firms based in New York, United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 28, 2026 156 companies tracked

RevenueBase identified 156 investigative consulting firms headquartered in New York, United States as of September 2026 and tracks 4,919 professional contacts across them, including 1,153 with verified work emails. Across the United States, New York is the largest hub for this category.

This list covers investigative consulting firms headquartered in New York, United States, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 28, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, 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 HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 28, 2026 86% judged on-target in blind review

156Companies

4,919Contacts tracked

1,153Verified emails

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The 25 largest investigative consulting firms based in New York, United States

Ranked by team size

Top 25 of 156 investigative consulting firms based in New York, United States, ranked by team size, largest first. Data refreshed Sep 28, 2026. RevenueBase Smart Search rates how each company's information relates to investigative consulting firms: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#	Company	RevenueBase Smart Search	Headquarters	Employees	Contacts
1	Guardsmark	Indirect evidence	New York, NY, United StatesHQ checked Sep 28, 2026	10001+	1,375 contacts →
	Indirect evidence “Guardsmark, LLC provides security services.” Source: RevenueBase Database · checked Sep 28, 2026
2	Keystone	Partial evidence	New York, NY, United StatesHQ checked Sep 28, 2026	201-500	423 contacts →
	Partial evidence “Keystone is an innovative strategy, economics, and technology consulting firm delivering transformative ideas and novel solutions to global brands and law firms on leading-edge…” Source: RevenueBase Database · checked Sep 28, 2026
3	Vcheck	Partial evidence	New York, NY, United StatesHQ checked Sep 28, 2026	201-500	336 contacts →
	Partial evidence “Vcheck is a global investigations firm that helps institutions protect their investments by providing intelligence on individuals and entities.” Source: RevenueBase Database · checked Sep 28, 2026
4	Guidepost Solutions	Indirect evidence	New York, NY, United StatesHQ checked Sep 28, 2026	201-500	268 contacts →
	Indirect evidence “We stand at the forefront of leadership, insight, and guidance in a world marked by complexity and uncertainty.” Source: RevenueBase Database · checked Sep 28, 2026
5	T&m Usa, LLC	Strong evidence	New York, NY, United StatesHQ checked Sep 28, 2026	201-500	216 contacts →
	Strong evidence “T&M USA provides seamlessly integrated executive protection, investigative and consulting services.” Source: RevenueBase Database · checked Sep 28, 2026
6	Research Nester Analytics	Partial evidence	New York, NY, United StatesHQ checked Sep 28, 2026	51-200	191 contacts →
	Partial evidence “Research Nester is a global consulting firm that works with the most aspirational facilitators to define the future market strategies.” Source: RevenueBase Database · checked Sep 28, 2026
7	LECG	Partial evidence	New York, United StatesHQ checked Sep 28, 2026	1,001-5,000	181 contacts →
	Partial evidence “LECG is a global litigation; economics; consulting and business advisory; and governance, assurance, and tax expert services firm.” Source: RevenueBase Database · checked Sep 28, 2026
8	Silverseal	Indirect evidence	New York, NY, United StatesHQ checked Sep 28, 2026	501-1,000	159 contacts →
	Indirect evidence “Silverseal is a comprehensive security solutions firm with worldwide affiliations that can provide global security services in a highly professional manner.” Source: RevenueBase Database · checked Sep 28, 2026
9	Beau Dietl & Associates	Partial evidence	New York, NY, United StatesHQ checked Sep 28, 2026	51-200	129 contacts →
	Partial evidence “Beau Dietl & Associates is a premier private investigation firm based in New York City with offices in New Jersey, Florida, and California.” Source: RevenueBase Database · checked Sep 28, 2026
10	Nardello & CO	Indirect evidence	New York, NY, United StatesHQ checked Sep 28, 2026	51-200	112 contacts →
	Indirect evidence Source: RevenueBase Database · checked Sep 28, 2026
11	RLN US LLP	Partial evidence	New York, NY, United StatesHQ checked Sep 28, 2026	51-200	97 contacts →
	Partial evidence “RLN US LLP is a consulting firm helping clients navigate complex issues related to business operations.” Source: RevenueBase Database · checked Sep 28, 2026
12	Seda Experts	Strong evidence	New York, United StatesHQ checked Sep 28, 2026	51-200	85 contacts →
	Strong evidence “SEDA Experts is a financial services consulting firm specializing in disputes and investigations.” Source: RevenueBase Database · checked Sep 28, 2026
13	AJ Squared Security	Indirect evidence	New York, NY, United StatesHQ checked Sep 28, 2026	201-500	82 contacts →
	Indirect evidence “AJ Squared Security, Inc.(AJ2), is a privately owned security organization founded in May 2003 and incorporated in November 2003.” Source: RevenueBase Database · checked Sep 28, 2026
14	Blue Heron Research Partners	Indirect evidence	New York, NY, United StatesHQ checked Sep 28, 2026	51-200	75 contacts →
	Indirect evidence “Blue Heron Research Partners is an international leader in qualitative due diligence.” Source: RevenueBase Database · checked Sep 28, 2026
15	Integrated Security Services	Indirect evidence	New York, NY, United StatesHQ checked Sep 28, 2026	201-500	72 contacts →
	Indirect evidence “Integrated Security Services, Inc.” Source: RevenueBase Database · checked Sep 28, 2026
16	City Safe Partners	Indirect evidence	New York, NY, United StatesHQ checked Sep 28, 2026	201-500	68 contacts →
	Indirect evidence “At CITY SAFE PARTNERS SECURITY, we create solutions and put systems in place to ensure that people and businesses are secure.” Source: RevenueBase Database · checked Sep 28, 2026
17	Dubin Research & Consulting DRC	Partial evidence	New York, NY, United StatesHQ checked Sep 28, 2026	11-50	63 contacts →
	Partial evidence “Dubin Research & Consulting (DRC) has distinguished itself as one of the finest consulting firms in the nation, specializing in jury selection, demonstrative aids, focus groups…” Source: RevenueBase Database · checked Sep 28, 2026
18	Hilton Global Associates INC	Partial evidence	New York, NY, United StatesHQ checked Sep 28, 2026	51-200	42 contacts →
	Partial evidence “Hilton Global Associates is a professional investigative research firm providing expert due diligence and unparalleled client service.” Source: RevenueBase Database · checked Sep 28, 2026
19	Hyde Park Investment Services, INC	Indirect evidence	New York, NY, United StatesHQ checked Sep 28, 2026	11-50	42 contacts →
	Indirect evidence “HPIS helps decision-makers increase productivity by delegating their analytical tasks to us.” Source: RevenueBase Database · checked Sep 28, 2026
20	Quinlan Partners	Partial evidence	New York, NY, United StatesHQ checked Sep 28, 2026	11-50	35 contacts →
	Partial evidence “Quinlan Partners is a global due diligence, investigations and business intelligence firm whose team of top former investigative journalists, corporate intelligence and…” Source: RevenueBase Database · checked Sep 28, 2026
21	Corporate Resolutions INC	Partial evidence	New York, NY, United StatesHQ checked Sep 28, 2026	11-50	29 contacts →
	Partial evidence “Corporate Resolutions Inc.(CRI) specializes in background investigations for the alternative investment and legal communities.” Source: RevenueBase Database · checked Sep 28, 2026
22	Polaris Corporate Risk Management	Partial evidence	New York, NY, United StatesHQ checked Sep 28, 2026	51-200	27 contacts →
	Partial evidence “Bringing more than 50 years of global security and investigations experience, Polaris is an industry leader in the corporate risk management space.” Source: RevenueBase Database · checked Sep 28, 2026
23	Portman Square Group	Indirect evidence	New York, NY, United StatesHQ checked Sep 28, 2026	11-50	27 contacts →
	Indirect evidence “Portman Square Group (PSG) is a premier full-service business intelligence and strategic communications firm adept at navigating the complexities of today's global economy.” Source: RevenueBase Database · checked Sep 28, 2026
24	Summit Ridge Group, LLC	Indirect evidence	New York, NY, United StatesHQ checked Sep 28, 2026	11-50	25 contacts →
	Indirect evidence Source: RevenueBase Database · checked Sep 28, 2026
25	Renaissance Associates, LTD	Indirect evidence	New York, NY, United StatesHQ checked Sep 28, 2026	11-50	24 contacts →
	Indirect evidence Source: RevenueBase Database · checked Sep 28, 2026

RevenueBase Smart Search

RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: investigative consulting firms. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.

Strong evidence: The company's own public description of its business names investigative consulting firms.
Partial evidence: Its own public description names part of investigative consulting firms, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name investigative consulting firms. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.

RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.

Showing 25 of 156 investigative consulting firms based in New York, United States

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Investigative consulting firms based in New York, United States at a glance

As of Sep 28, 2026

23.4%Verified-email coverage

31.5Average contacts per company

11-50Median size (employees)

Sep 28, 2026Page data refreshed

Companies by employee count

1-10

11-50

51-200

201-500

501-1,000

1,001-5,000

10001+

Email recency for this list is measured across the whole United States list rather than for New York, so it is reported there. Company counts and contact totals on this page are exact for New York, over 156 companies.

How this list was built

Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among investigative consulting firms, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.

Source: The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
What qualifies: Companies headquartered in New York, United States whose own description of what they do matches “investigative consulting firms”. Matching reads each company's description, not its industry code or its name.
RevenueBase Smart Search: RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names investigative consulting firms), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
What we exclude: Companies whose own description does not clearly place them among investigative consulting firms, and records with no verified work email. Companies headquartered outside New York are excluded even when they keep an office there.
Match quality: In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
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 listed company carries at least one verified work email, 1,153 across the full list. 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 28, 2026. Lists refresh periodically as the graph is re-checked.
Corrections: Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.

Investigative consulting firms by metro in the United States

Frequently asked

What is RevenueBase Smart Search?

RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names investigative consulting firms, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.

How many investigative consulting firms are there based in New York, United States?

RevenueBase identified 156 investigative consulting firms headquartered in New York, United States as of September 2026, matched on each company's own description of what it does rather than its industry code.

What is the largest company on this list?

Guardsmark, headquartered in New York, tops this list with the largest team on record.

Which city in the United States has the most investigative consulting firms?

New York leads the United States with 156 headquartered companies, followed by Houston (78) and Washington (73).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 1,153 verified decision-maker contacts tracked across these 156 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 28, 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 Smart Search, 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.