Company lists · Data refreshed September 2026

Top 25 Custom synthesis companies based in the United States

Name: Custom synthesis companies based in the United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 19, 2026 343 companies tracked

RevenueBase identified 343 custom synthesis companies headquartered in the United States as of September 2026 and tracks 14,589 professional contacts across them, including 4,906 with verified work emails. San Diego is the largest hub.

This list covers custom synthesis companies headquartered in the 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 19, 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 19, 2026 86% judged on-target in blind review

343Companies

14,589Contacts tracked

4,906Verified emails

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The 25 largest custom synthesis companies based in the United States

Ranked by team size

Top 25 of 343 custom synthesis companies based in the United States, ranked by team size, largest first. Data refreshed Sep 19, 2026. RevenueBase Smart Search rates how each company's information relates to custom synthesis companies: 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	Cambrex	Indirect evidence	East Rutherford, NJ, United StatesHQ checked Sep 19, 2026	1,001-5,000	1,294 contacts →
	Indirect evidence “Cambrex is a leading global contract development and manufacturing organization (CDMO) that provides drug substance development and manufacturing across the entire drug lifecycle…” Source: RevenueBase Database · checked Sep 19, 2026
2	Nitto Avecia	Indirect evidence	Milford, MA, United StatesHQ checked Sep 19, 2026	501-1,000	603 contacts →
	Indirect evidence “Oligonucleotides are giving rise to a new generation of therapeutics-and Nitto Avecia is helping lead the way.” Source: RevenueBase Database · checked Sep 19, 2026
3	Veranova	Indirect evidence	Devens, MA, United StatesHQ checked Sep 19, 2026	501-1,000	574 contacts →
	Indirect evidence “Veranova is a global leader in process development and manufacturing of active pharmaceutical ingredients (APIs), with a focus on specialty and complex chemistry for small…” Source: RevenueBase Database · checked Sep 19, 2026
4	SK Pharmteco	Indirect evidence	Rancho Cordova, CA, United StatesHQ checked Sep 19, 2026	1,001-5,000	540 contacts →
	Indirect evidence “Established in 2019 by SK Inc, SK pharmteco is a global contract development and manufacturing organization (CDMO) with operations across the U.S, Europe, and South Korea.” Source: RevenueBase Database · checked Sep 19, 2026
5	Monument Chemical	Partial evidence	Indianapolis, IN, United StatesHQ checked Sep 19, 2026	501-1,000	401 contacts →
	Partial evidence “Every day, our customers bring us their toughest chemistry challenges.” Source: RevenueBase Database · checked Sep 19, 2026
6	Olon USA	Indirect evidence	Concord, OH, United StatesHQ checked Sep 19, 2026	51-200	237 contacts →
	Indirect evidence “Who we are: On June 9, 2017, Olon S.p.A, a leading Active Pharmaceutical Ingredients (API) contract development and manufacturing organization (CDMO) and Generics supplier…” Source: RevenueBase Database · checked Sep 19, 2026
7	Spectrum Chemical Mfg. Corp	Indirect evidence	New Brunswick, NJ, United StatesHQ checked Sep 19, 2026	201-500	232 contacts →
	Indirect evidence “Spectrum Chemical Mfg.” Source: RevenueBase Database · checked Sep 19, 2026
8	Halo Pharmaceutical, INC	Indirect evidence	Whippany, NJ, United StatesHQ checked Sep 19, 2026	201-500	219 contacts →
	Indirect evidence “Halo Pharma is a leading provider of pharmaceutical services, including contract dosage form development, commercial manufacturing, and analytical services.” Source: RevenueBase Database · checked Sep 19, 2026
9	Adesis, INC	Indirect evidence	New Castle, DE, United StatesHQ checked Sep 19, 2026	51-200	182 contacts →
	Indirect evidence “Adesis Inc.” Source: RevenueBase Database · checked Sep 19, 2026
10	Ambiopharm	Partial evidence	North Augusta, SC, United StatesHQ checked Sep 19, 2026	501-1,000	174 contacts →
	Partial evidence “AmbioPharm is a global custom synthetic peptide CDMO founded in 2005 and headquartered in North Augusta, South Carolina, USA specializing in developing highly efficient…” Source: RevenueBase Database · checked Sep 19, 2026
11	Biospectra, INC	Indirect evidence	Bangor, PA, United StatesHQ checked Sep 19, 2026	201-500	152 contacts →
	Indirect evidence “BioSpectra Inc.(BSI), is a privately-owned manufacturer of premium pharmaceutical ingredients and bulk, cGMP fine chemicals, in service to many leading BioPharma companies around…” Source: RevenueBase Database · checked Sep 19, 2026
12	Seatex	Partial evidence	Rosenberg, TX, United StatesHQ checked Sep 19, 2026	201-500	147 contacts →
	Partial evidence “Extensive chemical synthesis, formulation, manufacturing, and technology expertise.” Source: RevenueBase Database · checked Sep 19, 2026
13	Apicore Pharmaceuticals	Indirect evidence	East Brunswick, NJ, United StatesHQ checked Sep 19, 2026	501-1,000	141 contacts →
	Indirect evidence “Apicore LLC, a wholly owned subsidiary of RK Pharma Inc is a leading process R&D and API manufacturing service provider for the worldwide pharmaceutical industry.” Source: RevenueBase Database · checked Sep 19, 2026
14	NJ Bio, INC	Indirect evidence	Princeton, NJ, United StatesHQ checked Sep 19, 2026	51-200	139 contacts →
	Indirect evidence “NJ Bio Inc.” Source: RevenueBase Database · checked Sep 19, 2026
15	Ortec INC	Partial evidence	Easley, SC, United StatesHQ checked Sep 19, 2026	201-500	139 contacts →
	Partial evidence “Ortec is a custom chemical manufacturing and research company that helps our customers reach their market goals through our Technical Expertise, Quality Systems, Regulatory…” Source: RevenueBase Database · checked Sep 19, 2026
16	J-Star Research, INC	Indirect evidence	South Plainfield, NJ, United StatesHQ checked Sep 19, 2026	51-200	112 contacts →
	Indirect evidence “Founded in 1996 J-STAR Research, Inc.” Source: RevenueBase Database · checked Sep 19, 2026
17	Camco Chemical	Indirect evidence	Florence, KY, United StatesHQ checked Sep 19, 2026	201-500	112 contacts →
	Indirect evidence “Camco Chemical brings over 65 years of expertise as a trusted leader in chemical contract manufacturing, contract packaging, and supply chain solutions.” Source: RevenueBase Database · checked Sep 19, 2026
18	CJB Industries, INC	Indirect evidence	Valdosta, GA, United StatesHQ checked Sep 19, 2026	51-200	110 contacts →
	Indirect evidence “At CJB Industries, we deliver solutions to your chemical manufacturing challenges.” Source: RevenueBase Database · checked Sep 19, 2026
19	Ascent Chemicals	Partial evidence	Schaumburg, IL, United StatesHQ checked Sep 19, 2026	51-200	103 contacts →
	Partial evidence “We are an elite family of companies that solve complex problems for our customers through specialty chemical manufacturing and tolling.” Source: RevenueBase Database · checked Sep 19, 2026
20	Wiley Companies	Partial evidence	Coshocton, OH, United StatesHQ checked Sep 19, 2026	201-500	102 contacts →
	Partial evidence “Wiley Companies is an ISO 9001:2015 and FSSC certified custom chemicals and food ingredients manufacturer with facilities in Coshocton, OH, and New Albany, OH.” Source: RevenueBase Database · checked Sep 19, 2026
21	Ethox Chemicals	Indirect evidence	Greenville, SC, United StatesHQ checked Sep 19, 2026	201-500	82 contacts →
	Indirect evidence “Ethox Chemicals, A Syntha Group Company Founded in 1938 by Fred Wilson, Sr.” Source: RevenueBase Database · checked Sep 19, 2026
22	Arzeda	Indirect evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	51-200	79 contacts →
	Indirect evidence “Arzeda, The Protein Design Company™, is a synthetic biology company that creates novel proteins, enzymes and specialty chemical products that compete on performance, cost and…” Source: RevenueBase Database · checked Sep 19, 2026
23	Synsmart	Indirect evidence	Newtown, PA, United StatesHQ checked Sep 19, 2026	51-200	78 contacts →
	Indirect evidence “Founded in 2014, SynSmart has made its name in chemistry services for early-stage discovery projects as well as collaborative scale-up and manufacturing support services.” Source: RevenueBase Database · checked Sep 19, 2026
24	CSBIO	Partial evidence	Menlo Park, CA, United StatesHQ checked Sep 19, 2026	51-200	76 contacts →
	Partial evidence “CSBio is a leading peptide and peptide synthesizer manufacturing company located in Silicon Valley, California.” Source: RevenueBase Database · checked Sep 19, 2026
25	Regis Technologies	Indirect evidence	Morton Grove, IL, United StatesHQ checked Sep 19, 2026	51-200	75 contacts →
	Indirect evidence “Regis Technologies, Inc.” Source: RevenueBase Database · checked Sep 19, 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: custom synthesis companies. 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 custom synthesis companies.
Partial evidence: Its own public description names part of custom synthesis companies, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name custom synthesis companies. 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 343 custom synthesis companies based in the United States

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Custom synthesis companies based in the United States at a glance

As of Sep 19, 2026

33.6%Verified-email coverage

42.5Average contacts per company

11-50Median size (employees)

5.2%Largest-city concentration · San Diego

Sep 19, 2026Page data refreshed

Companies by employee count

1-10

116

11-50

101

51-200

201-500

501-1,000

1,001-5,000

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 343 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 custom synthesis companies, 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 the United States whose own description of what they do matches “custom synthesis companies”. 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 custom synthesis companies), 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 custom synthesis companies, and records with no verified work email. Companies headquartered outside United States 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, 4,906 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 19, 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.

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 custom synthesis companies, 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 custom synthesis companies are there based in the United States?

RevenueBase identified 343 custom synthesis companies headquartered in the 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?

Cambrex, headquartered in East Rutherford, tops this list with the largest team on record.

Which city has the most custom synthesis companies?

San Diego leads with 18 headquartered companies, followed by Wilmington (8) and New York (7).

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 4,906 verified decision-maker contacts tracked across these 343 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 19, 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.