Enriching from Public Databases: The Complete B2B Guide

Your CRM is full of half-empty company records. Missing industry codes, rough headcount estimates, outdated executives. You spend more time hunting for information than actually prospecting. Yet a large chunk of that data already exists — for free, legally, updated daily — in public databases anyone can access.

The problem is that nobody explains how to use them effectively. What’s in each database? What can you actually use for B2B outreach? Where do public sources fall short, and what do you need to fill the gaps?

This guide answers all of it — from mapping available sources to building a complete enrichment workflow, with GDPR rules laid out clearly along the way.

Enrich your B2B data directly in Google Sheets

Find verified emails and phone numbers for your prospects from LinkedIn — without leaving your spreadsheet.

Try for free →

What counts as a public database in B2B?

A public database is any registry or directory made accessible by a government authority or public body, usually as part of open data legislation. In the UK, this includes Companies House and the Financial Conduct Authority. In the US, it includes SEC EDGAR and state-level business registries. Across the EU, every member state maintains its own equivalent.

For B2B prospecting, these databases matter because they systematically register all active companies — their legal identity, registered executives, industry classification, and in some cases financial filings. All of this is updated regularly, at no cost.

The critical distinction to keep in mind: public databases deliver firmographic data (information about the company as an entity), not contact data (the email or phone number of a specific decision-maker). Understanding this limit is what lets you use these sources at their actual value — and know exactly when to layer in additional enrichment.

The 5 public databases every B2B team should know

1. Companies House (UK) — the backbone of UK firmographic data

Companies House is the UK’s official register of companies, maintained by the government. Every limited company, LLP, and public company in the UK must be registered here. The registry holds records on over 5 million companies with daily updates.

What it contains: company registration number, registered address, company type and status (active, dissolved, liquidation), SIC code (sector), incorporation date, filing history, and — crucially — the names and appointment dates of all directors and persons with significant control (PSC).

What it doesn’t contain: professional email addresses, direct phone numbers, or social media profiles.

The Companies House API is completely free and requires no authentication for basic queries. Bulk data is also available via Companies House data products.

Typical use case: Sarah, a Sales Ops manager at a UK SaaS company, needs to verify which companies in her pipeline are still active and identify the right director title for each. She queries the Companies House API in bulk using registration numbers — adding current director names, SIC codes, and filing status to every record in under an hour.

2. SEC EDGAR (US) — filings and financials for public companies

For B2B teams targeting US companies, the SEC’s EDGAR database is the go-to public financial registry. All public companies must file quarterly and annual reports (10-Q, 10-K), proxy statements, and M&A filings — all freely searchable.

What it gives you: executive names and compensation (from proxy filings), revenue and headcount figures, subsidiary structures, and significant business events like acquisitions or leadership changes.

EDGAR is best suited for enterprise-level prospecting targeting large public companies. For SMBs and private companies, state-level registries provide basic identification data but far less financial detail.

3. State and EU business registries — the foundation for SMB targeting

Each US state maintains its own business registry (Secretary of State filings), and each EU country runs its official commercial register: Companies House for the UK, the INPI/RCS for France, the Handelsregister for Germany, the Kamer van Koophandel (KVK) for the Netherlands.

These registries all provide: legal business name, registration number, registered address, company type, and in most cases the names of registered executives or directors. Access varies — some offer free APIs (Companies House, French INPI), others charge per query.

For pan-European prospecting, aggregators like Pappers (France-focused) consolidate data from multiple national registries into a single interface and API, simplifying firmographic enrichment across borders.

4. Official gazette publications — business signals in real time

Most countries publish official announcements of significant company events: new incorporations, leadership appointments, insolvencies, and M&A activity. In the UK, this is the London Gazette. In France, it’s the BODACC. In the US, state publications and the Federal Register serve a similar function.

For prospecting, these publications are a gold mine of business signals. A company that just appointed a new CEO is in transformation — ideal timing to introduce a new tool. A business opening a new office is growing. A company entering liquidation proceedings should be removed from your pipeline immediately.

Many of these signals are accessible via free APIs or RSS feeds, making automated pipeline monitoring feasible without significant technical investment.

5. LinkedIn and company websites — the complementary public layer

Beyond official registries, two “public” sources are widely used for B2B enrichment: publicly accessible LinkedIn profiles and company website pages (About, Contact, Team).

LinkedIn gives you: job titles and seniority of decision-makers, career history, approximate team size, stated company sector, and skills — all publicly visible for profiles without strict privacy settings.

Company websites provide: general contact email, headquarters phone number, business description, detectable technology stack, and social media links. Derrick’s Website Email & Social Media Extractor automates this collection from any URL, while the Website Tech Lookup feature identifies the technology stack a company is running — useful for tech-qualified outreach sequences.

What public databases don’t cover (and how to fill the gaps)

Here’s what rarely gets stated plainly: public databases are excellent for firmographic foundations, but they contain no individual contact data usable for direct prospecting.

The table below maps exactly what you’ll find in each source — and what you won’t:

To find a verified professional email for an executive you’ve identified through a public registry, you need an email finder — like Derrick’s Email Finder feature, which finds and verifies the professional address from first name, last name, and company domain. For direct phone numbers, Derrick’s Phone Finder retrieves them from the prospect’s LinkedIn profile.

Step-by-step enrichment workflow using public databases

Here’s the full workflow to go from a raw target list to a clean, enriched, outreach-ready prospect base.

Step 1: Build your target list using firmographic criteria

Define your ICP in objective terms: industry (SIC code), company size (headcount range), legal type, geography, incorporation date, active status. Use the relevant public registry or an aggregator to filter and export a list of matching companies with their registration numbers.

Expected output: A CSV of 500–5,000 companies with IDs, legal names, addresses, sector codes, and headcount ranges.

Step 2: Enrich missing firmographic fields

Take the company IDs from Step 1 and query the appropriate registry API to fill gaps — exact legal form, subsidiaries, incorporation date, secondary locations. This is what enables precise segmentation (startup vs. enterprise, services vs. manufacturing).

If you use Google Sheets as your working environment, Derrick’s LinkedIn Company Scraper retrieves company data from a LinkedIn company page URL, and the SimilarWeb Insights feature adds web traffic and audience data for each domain — useful for sizing companies that don’t publish financials.

Expected output: Each company record now has the complete firmographic data needed for segmentation and qualification.

Step 3: Identify decision-makers via public sources

For each target company, identify the relevant contacts using two complementary approaches:

Via official registries (Companies House, EDGAR): pull the names of registered directors or executives. This is the most reliable source for SMBs where the CEO or founder is your direct target.

Via LinkedIn: search for people holding the title that matches your persona (Head of Marketing, VP Sales, CTO…). Derrick’s LinkedIn Profile Scraper enriches a LinkedIn profile URL with 50+ attributes: current title, experience, skills, email, and phone number.

Expected output: For each target company, you have the name and LinkedIn profile of the relevant decision-maker(s).

Step 4: Enrich contact data

This is where public databases reach their limit. No public registry provides verified professional emails or direct phone numbers. Run your identified contacts through an email finder — combining first name, last name, and company domain — to obtain a verified professional address.

Before any campaign, pass your existing list through an email verifier to remove invalid addresses and protect your sender reputation. According to industry benchmarks, up to 30% of B2B email addresses become invalid within 12 months.

Expected output: A prospect base with verified professional emails, ready for outbound prospecting.

Step 5: Clean and validate the database

Before deploying your enriched base, apply a cleaning pass: remove duplicates, normalize company names, and purge dissolved or insolvent companies (cross-reference with official gazette publications). B2B data degrades at 22–30% per year — even a base built from official sources requires regular maintenance to stay usable.

Public databases and GDPR: what the rules actually say

Using public data for commercial prospecting is explicitly addressed by GDPR — and it is permitted, under the right conditions. The key legal basis is legitimate interest (Article 6.1.f).

Enriching from publicly available data — public LinkedIn profiles, company websites, official business registries — is allowed under GDPR, provided the purpose is B2B prospecting and you respect data subjects’ rights.

Three conditions must be met for legitimate interest to hold:

1. The purpose must be specific and documented. “Commercial prospecting” isn’t enough. Document your target (e.g., “CFOs at UK manufacturing SMBs with 50–250 employees”), the channel (cold email), and the relevance of your offer to the recipient’s role.

2. The processing must be proportionate. Only collect data strictly necessary for your stated purpose. Building detailed profiles that go beyond prospecting needs can be challenged as excessive processing.

3. Data subjects’ rights must be honoured. Inform prospects on first contact where their data came from, provide a simple opt-out, and delete inactive prospect records after a maximum of 3 years — the standard retention period recommended by supervisory authorities including the ICO.

For pure firmographic data (registration numbers, SIC codes, registered addresses) that doesn’t identify a specific individual, GDPR doesn’t apply directly. GDPR obligations are triggered the moment you enrich with nominative data — executive names, professional email addresses — that enables identification of a natural person.

For reference, the GDPR compliance glossary covers the key concepts, and our article on GDPR and cold emailing addresses the outreach side specifically.

Common mistakes when enriching from public sources

Problem 1: Treating public data as outreach-ready

Impact: You build a large database that’s useless for prospecting — public records alone give you no way to contact decision-makers directly.

Solution: Use the two-stage workflow above. Public databases handle firmographic targeting; contact enrichment tools handle emails and phone numbers.

Problem 2: Using stale data without verification

Impact: You run campaigns to dissolved companies or executives who moved on months ago, damaging deliverability and wasting outreach sequences.

Solution: Cross-reference your company list with official gazette publications for status checks, and enrich LinkedIn profiles to detect role changes. Schedule a quarterly refresh of your database, even for data sourced from official registries.

Problem 3: Skipping the transparency obligation

Impact: GDPR non-compliance, risk of ICO or supervisory authority action, reputational damage with enterprise prospects who conduct vendor compliance reviews.

Solution: Include a data source mention and functional unsubscribe link in every prospecting email. For contacts sourced from a public registry, state this explicitly in your first message — for example: “I found your details on Companies House / through your company’s LinkedIn page.”

Problem 4: Over-enriching beyond what’s needed

Impact: Harder-to-maintain database, unnecessary enrichment costs, potential disproportionate processing under GDPR.

Solution: Define required fields before enriching. For standard outbound prospecting: company name, sector, headcount, decision-maker name, verified email, and optionally a phone number. Full legal history and detailed financial data are rarely necessary for first-touch outreach.

Key takeaways

• Public business registries (Companies House, SEC EDGAR, national EU registers) cover their entire business landscapes with reliable, regularly updated firmographic data — for free.
• They contain no professional emails or direct phone numbers — these must come from a contact enrichment layer.
• The optimal workflow combines firmographic targeting via public databases with contact enrichment via LinkedIn and email finder tools.
• GDPR permits reuse of public business data for B2B prospecting under legitimate interest, subject to proportionality and transparency obligations.
• B2B data degrades at 22–30% annually — schedule regular refreshes, even for data sourced from official registries.

Conclusion: A solid foundation, not a finished database

Public databases are one of the most underused assets in B2B sales. They provide a reliable firmographic foundation — updated daily, free to access — that many paid data providers simply aggregate and resell at a premium.

But they’re a starting point, not a finished product. They tell you which companies to target, their size, their sector, their registered executives. What they don’t give you is a way to reach those people directly.

That’s where contact enrichment comes in. With Derrick, you can move from a target list built via public registries to a prospect base with verified emails and phone numbers — managed entirely in Google Sheets, without stitching together multiple tools.

From public registry to qualified contact, in Google Sheets

Import your company lists and enrich emails, phone numbers, and firmographic data in a few clicks — no exports, no manual work.

Try for free →

FAQ

Can you use Companies House data for B2B prospecting? Yes. Companies House data is publicly available and free to use. Reusing it for B2B prospecting is permitted under GDPR’s legitimate interest basis, provided you inform contacts on first outreach where their data came from and offer a straightforward opt-out.

What’s the difference between firmographic data and contact data? Firmographic data (registration numbers, SIC codes, registered addresses) identifies a business entity and generally doesn’t identify a specific individual — GDPR typically doesn’t apply directly. Contact data (professional email, direct phone, executive name) identifies a natural person and is fully subject to GDPR, requiring a documented legal basis.

Is Companies House alone enough for B2B prospecting? No. Companies House is excellent for validating that a company is active, identifying its directors, and checking its legal status. But it provides no professional email addresses or direct phone numbers. For outbound prospecting, it must be paired with a contact enrichment tool.

How often should you refresh a database built from public sources? At minimum quarterly. B2B data degrades at 22–30% per year through role changes, company moves, and closures. Public registries themselves update daily or weekly — but your enriched database needs active maintenance to stay accurate and GDPR-compliant.

Does GDPR apply to executive names found in public registries? Yes. Even if the name appears in a public registry like Companies House or SEC EDGAR, using it for commercial prospecting constitutes processing of personal data under GDPR. You must document your legitimate interest, inform the person on first contact, and honour any opt-out request promptly.