Cybersecurity Companies in Reading: 28 Active Firms (2026)
Cybersecurity companies in Reading provide security software, managed protection, testing and advisory services for organisations in the Thames Valley.
Buying decisions in this market tend to sit with security, infrastructure and risk teams rather than general IT procurement alone. Reading-area suppliers typically sell into mid-market and enterprise buyers, with some public-sector and essential-service work where auditability matters. The commercial centre of gravity is service-led: managed detection, incident readiness, penetration testing, cloud security review and compliance advisory, often wrapped around recurring retainers or subscription licences. Engagements are rarely impulse purchases; they tend to involve technical scoping, evidence of practitioner credentials and procurement checks around GDPR, NIS obligations and operational resilience.
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Reading has 28 active trading cybersecurity companies, making it a compact Thames Valley cluster rather than a broad national sample. Reported headcount across the cohort totals 424 people, so the local employment footprint is visible but still weighted toward specialist teams rather than large employers. The pattern fits a town serving enterprise, cloud and public-sector buyers across the Thames Valley: enough supplier density for procurement choice, but not the scale of a national cyber hub.
Cyber security suppliers in Reading do not usually operate under a sector-wide licence, but their clients pull them into regulated workflows. GDPR and ICO guidance shape incident handling, evidence trails and data-processing controls; the NIS regime reaches operators of essential services and relevant digital service providers, including cloud, search and marketplace models. Planned reforms through the Cyber Security and Resilience Bill point toward closer oversight of managed service providers and faster reporting of harmful breaches. techUK and the UK Cyber Security Council also help set the terms buyers use in tenders and assurance reviews.
Reading’s cyber suppliers appear likely to remain service-heavy, with software used to support monitoring, testing and compliance rather than replacing advisory work outright. Buyers in regulated or essential-service settings tend to value evidence, responsiveness and sector familiarity, which favours providers that can pair tooling with named accountability. Scale-up scarcity may keep acquisition interest focused on specialist capability rather than revenue volume alone. At the same time, tighter breach-reporting expectations and managed-service scrutiny are likely to raise the cost of weak process discipline.
What’s in the file
One row per company, 50+ columns — everything below plus each company’s verified directors, from Companies House filings.
Company data
Verified directors — included
28
Active firms
2026
3
Above £5M
reported turnover
2
Since 2022
new incorporations
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Key facts
About 10% of the trading cohort reports turnover above £5M (3 of 28 firms) — the rest sits below that revenue band.
7% of the cohort was incorporated since 2022 (2 firms), so a sizeable share is in its first few filing cycles.
The Network and Information Systems Regulations 2018 cover operators of essential services and relevant digital service providers, including online marketplaces, online search engines and cloud computing services.
The ICO is the competent authority for relevant digital service providers and can issue fines of up to £17 million in the most serious cases.
Planned Cyber Security and Resilience Bill reforms would bring medium and large managed service providers into scope and require quicker reporting of harmful cyber breaches.
Government 2025 sectoral analysis estimates 2,165 active UK firms providing cyber security products and services, with £13.2 billion of revenue in the most recent financial year.
A 2026 government factsheet says the UK was “the most targeted country in Europe for cyber attacks” in 2024, framing demand as threat-led as well as IT-renewal-led.
Top Reading Cybersecurity companies
Provides cyber security consultancy and managed security services, including security audits, risk assessments, penetration testing, threat detection and response, security operations centre…
Sells to businesses and public-sector organisations with complex IT, cloud or operational technology environments, especially those with cyber security, incident response, data privacy and compliance…
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Develops and provides cybersecurity software and cloud services including email security, network firewalls, web application protection, data backup, and managed XDR. Products protect email,…
Serves businesses of all sizes, IT and security teams, and managed service providers needing cybersecurity across email, applications, networks and data, including small businesses and Microsoft 365…
Financial Health
N/AN/A
Location
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Provides cyber security consultancy and managed security services, including security architecture, risk assessments, penetration testing, security operations centre monitoring, threat detection and…
Serves B2B organisations with complex, highly regulated environments, including those operating critical business infrastructure and needing support across cloud, on-premise and operational…
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Computed from 3 filingsProvides managed services and consulting for secure data transfer, managed file transfer, data integration and orchestration. Implements and supports software for automated workflows, API…
Serves enterprise organisations worldwide, including multinational corporations and government-owned public bodies, with buyers responsible for data security, integration, file transfer, automation…
Financial Health
DistressedDistressed · 0% CAGR over 2y
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Provides endpoint management and cybersecurity software that gives organisations real-time visibility and control over devices. Platform supports asset discovery, vulnerability monitoring, patch…
Sells to enterprise IT and security leaders in security-conscious organisations, including energy, financial services, healthcare, manufacturing, retail and technology firms, plus federal, state and…
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Computed from 5 filingsProvides managed IT services and technical support for businesses, including cloud services, cybersecurity, device management, Apple and Jamf support, and IT project delivery. Also offers IT…
Serves small to mid-sized businesses in Reading, Oxford and surrounding areas, including marketing and creative firms, associations, in-house marketing teams, healthcare, charities, insurers, media…
Financial Health
WeakWeak · 0% CAGR over 4y
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Computed from 5 filingsDevelops digital forensic software and platforms for extracting, analysing and managing data from mobile devices and cloud sources. Provides tools such as XRY and XAMN, along with training,…
Serves law enforcement, military, border control and corrections agencies, plus eDiscovery organisations, targeting forensic specialists, digital investigators, frontline personnel and programme or…
Financial Health
StrongStrong · Growing, Hiring · 15% CAGR over 4y
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Develops data protection, backup, and recovery software for cloud, virtual, physical, and SaaS environments. Provides platforms and services for securing, replicating, and restoring data across…
Serves businesses of all sizes, service providers and public-sector organisations, especially IT and security teams in government, education, financial services, insurance and healthcare.
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Develops data protection and backup software for cloud, virtual, physical and SaaS environments. Provides backup, recovery, replication and ransomware recovery tools, including services for Microsoft…
Serves enterprises, small businesses, service providers and public-sector organisations, targeting IT, security and executive teams in government, education, financial services, insurance and…
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Computed from 3 filingsProvides consulting, implementation and managed IT services focused on Microsoft technologies. Delivers solutions including Microsoft 365, Dynamics 365, Power Platform, AI Copilot, project portfolio…
Serves B2B and public-sector organisations using Microsoft technologies, including construction, education, financial services, government, healthcare, manufacturing, not-for-profit, police and…
Financial Health
DistressedDistressed
Location
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Computed from 4 filingsSupplies data communication, networking, cabling and AV/IT infrastructure products via catalogue and online, and provides design, deployment, integration and managed services for enterprise networks,…
Serves enterprise and public-sector IT buyers across global industries, including data centres, finance, healthcare, education, government, manufacturing, retail, transportation, utilities, defence,…
Financial Health
HealthyHealthy · -5% CAGR over 3y
Location
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Computed from 5 filingsFinancial Health
WeakWeak · -71% CAGR over 4y
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Computed from 5 filingsProvides managed IT services and technology consulting, including cloud and Microsoft 365 solutions, cybersecurity, governance and compliance, disaster recovery, data analytics, web design and…
Serves businesses and organisations seeking managed IT, Microsoft cloud, cybersecurity, web development, digital marketing, data, compliance and digital transformation support.
Financial Health
StrongStrong · Hiring · 41% CAGR over 4y
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Computed from 5 filingsDevelops cybersecurity software for managing and analysing security data. Products include security data pipeline management tools and SIEM platforms that collect, normalise, route and analyse log…
Serves government, public sector and commercial organisations, from SMEs to large enterprises, especially buyers in critical national infrastructure and other security-sensitive environments. Sells…
Financial Health
DistressedDistressed · -2% CAGR over 4y
Location
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Computed from 5 filingsDevelops cyber security software and infrastructure including zero‑trust network access, peer‑to‑peer VPN connectivity and quantum‑safe encryption. Provides secure cloud hosting and tools to protect…
Sells to SMEs, enterprises and public sector organisations with demanding communications security needs, including critical infrastructure operators, remote telemetry and IoT deployments, telecoms…
Financial Health
StrongStrong · Hiring · 9% CAGR over 4y
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Provides cyber security and risk management services including penetration testing, incident response, threat intelligence, managed detection and response, vulnerability management, security…
Serves large enterprises and government/public sector organisations, across financial services, legal/professional services, retail, transport, technology/media/telecoms, energy/utilities,…
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Develops data management and cyber resilience software that protects, backs up and recovers enterprise data across cloud, SaaS, hybrid and on‑premises systems, including tools for ransomware…
Serves large enterprises and public-sector organisations, especially in government, healthcare, financial services, education and other regulated industries, with buyers including IT, security, data…
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Computed from 5 filingsProvides cyber security consultancy services including security audits, testing and assessments, Cyber Essentials and other standards certification support, and managed cyber security services for…
Serves businesses and public-sector organisations in technology, government, defence, healthcare, national infrastructure and legal sectors, from small firms to larger organisations with information…
Financial Health
DistressedDistressed · -13% CAGR over 4y
Location
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Computed from 5 filingsProvides cybersecurity consulting and managed services, including penetration testing for web, mobile and AI systems, security assessments, managed SOC monitoring, incident response, compliance and…
Serves organisations needing cyber security and compliance support, including businesses, charities, education bodies, healthcare/NHS suppliers and regulated firms subject to frameworks such as DfE,…
Financial Health
StrongStrong · Hiring · 41% CAGR over 4y
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Provides managed IT and cybersecurity services, including cloud, endpoint and network security, SD‑WAN, data protection, threat prevention, and infrastructure monitoring. Also offers security…
Serves businesses and public-sector organisations needing network security support, including retail and POS operators, financial services and ATM networks, critical infrastructure, healthcare, cloud…
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Computed from 5 filingsProvides managed IT support and consultancy for businesses, including cloud services, Microsoft 365 and Azure deployment, cybersecurity monitoring, penetration testing, VoIP telephony, backup…
Serves businesses in Oxfordshire and the Thames Valley across all industries, with particular focus on biotechnology, biomedical and engineering organisations needing outsourced IT and security…
Financial Health
StrongStrong · Growing, Hiring · 4% CAGR over 4y
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Computed from 5 filingsProvides IT consulting and managed IT services, including service desk support, cloud migration, infrastructure modernisation, cybersecurity, DevOps, and automation. Delivers technology advisory,…
Serves UK businesses across industries, including SMBs and larger organisations in financial services, water/utilities and firms pursuing cloud, cybersecurity, automation or digital transformation…
Financial Health
StableStable
Location
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Computed from 5 filingsDevelops user activity monitoring software that records and analyses actions across computers, applications and servers to detect insider threats, support compliance, and generate real-time alerts,…
Serves large, distributed organisations and inter-agency partnerships, including police, healthcare, finance, retail, local government, life sciences, manufacturing, engineering and logistics teams…
Financial Health
StableStable · Hiring · 12% CAGR over 4y
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Computed from 5 filingsProvides managed IT support and cybersecurity services for businesses, including endpoint detection and response, multi‑factor authentication, email security and DNS filtering. Also supplies…
Sells to small and mid-sized businesses in Bracknell, Reading, Wokingham and wider Berkshire that need outsourced IT and cyber security support.
Financial Health
StableStable · Hiring · 12% CAGR over 4y
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Computed from 5 filingsProvides managed IT services including cloud hosting, managed infrastructure, cybersecurity, and data protection. Offers infrastructure monitoring through its Pulse360 platform, website and data…
Sells to businesses needing managed IT, cyber security, cloud infrastructure and data protection services, particularly SMEs and companies seeking support for on-premise, cloud or hybrid environments.
Financial Health
HealthyHealthy · Hiring · 6% CAGR over 4y
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Computed from 2 filingsServes large enterprises and public sector organisations, including manufacturers, transport operators, energy and resources firms, retailers, and healthcare or government bodies.
Financial Health
StableStable
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Computed from 3 filingsProvides managed cyber security services for small and medium-sized businesses, including 24/7 security operations centre monitoring, incident response support, compliance assistance, vulnerability…
Serves UK SMEs and growing businesses with 50-250 employees, especially Microsoft 365-centric organisations. Also targets MSP partners seeking to extend their security services portfolio.
Financial Health
DistressedDistressed · 67% CAGR over 1y
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Computed from 5 filingsProvides managed IT services including cloud hosting, infrastructure management, cybersecurity, and data protection. Offers monitoring and performance tools, managed public and private cloud…
Serves SMEs and other businesses with IT infrastructure needs, including organisations using on-premise, cloud or hybrid environments and seeking external support for security, hosting and data…
Financial Health
StableStable · 0% CAGR over 4y
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Computed from 3 filingsDevelops a software platform for data classification, privacy and sovereignty management. Provides tools to discover and classify sensitive data, enforce access controls, and protect data in transit…
Sells to enterprise data, security, privacy and compliance teams in organisations handling sensitive data across APIs, databases and cloud platforms, especially those managing data protection,…
Financial Health
StableStable · Hiring · 15% CAGR over 2y
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Computed from 4 filingsProvides IT infrastructure and technology services including hybrid cloud and datacentre solutions, cybersecurity, networking, managed IT services, hardware and software supply, and professional…
Serves businesses and organisations with internal IT, operations and leadership teams responsible for cloud infrastructure, cybersecurity, networking, Microsoft environments, workplace technology,…
Financial Health
StrongStrong · 53% CAGR over 2y
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Computed from 5 filingsProvides managed IT services for businesses, including user support, IT infrastructure management, cloud platform management and migration, cybersecurity services and vulnerability scanning, managed…
Sells to businesses needing outsourced IT support, including buyers of managed IT, cloud, cyber security, network and hosted telephony services. Targets organisations seeking ongoing IT management…
Financial Health
StableStable · Hiring · 5% CAGR over 4y
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Provides business IT services including cloud infrastructure, cyber security, network connectivity, modern workplace platforms and managed IT support. Designs, deploys and manages technology…
Sells to UK business and education organisations, particularly IT leaders in multi-site retail, creative, architecture, veterinary and professional services environments.
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Computed from 5 filingsDevelops investigation and intelligence management software. Provides the NIMBUS platform for digital forensics, case management, evidence tracking, task coordination, and reporting used by law…
Serves law enforcement agencies, government bodies and corporate security teams that manage investigations, intelligence, digital forensics, major crime cases, insider risk and enterprise cyber…
Financial Health
StableStable · Hiring · 41% CAGR over 4y
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Computed from 5 filingsProvides IT consulting and managed services including digital transformation strategy, cloud and infrastructure advisory, cybersecurity risk consulting, IT infrastructure implementation, cloud…
Serves businesses and organisations needing strategic IT guidance, digital transformation support, cloud and infrastructure planning, cybersecurity risk management, and ongoing IT operations support.
Financial Health
StrongStrong · Hiring · 60% CAGR over 4y
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Computed from 2 filingsProvides managed IT services for businesses, including IT support, cyber security, business continuity, server and network management, and connectivity and telephony solutions. Also delivers business…
Serves UK businesses outsourcing or switching IT support, including organisations needing managed IT, business continuity, cyber security, server, network, connectivity and telephony support.
Financial Health
WeakWeak · 0% CAGR over 1y
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Computed from 4 filingsProvides managed IT support, cybersecurity services, cloud and Microsoft 365 solutions, telecoms and internet connectivity, networking and Wi‑Fi infrastructure, hardware supply, and backup and…
Serves small and medium-sized businesses across the south of the UK, including dental and aesthetics practices, care homes, manufacturers, financial and legal firms, hospitality operators, charities…
Financial Health
HealthyHealthy · Growing, Hiring · 12% CAGR over 3y
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Computed from 3 filingsDevelops blockchain-based security software and infrastructure for managing digital assets and transactions. Provides cloud wallets, custody services, confidential computing, key management, and…
Serves businesses and organisations handling critical transactions, sensitive information and digital assets, particularly teams with security, regulatory compliance, blockchain, confidential…
Financial Health
StrongStrong · Hiring · 27% CAGR over 2y
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Computed from 3 filingsProvides managed IT support and consultancy for businesses, including network and workplace connectivity, cloud services, and security and compliance. Installs and maintains servers and PCs, performs…
Serves businesses in Berkshire and surrounding areas that need outsourced IT support, workplace connectivity, security and compliance, consultancy, and cloud services.
Financial Health
StableStable · 0% CAGR over 2y
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Computed from 2 filingsProvides managed IT support and consultancy for businesses, including system monitoring, cybersecurity, cloud services, workplace connectivity, and server management. Implements and maintains IT…
Targets SMEs and owner-managed businesses in Berkshire/Newbury that need an outsourced IT partner for staff PCs, servers, connectivity, security, compliance and cloud environments.
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StableStable · 0% CAGR over 1y
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Computed from 5 filingsProvides IT consultancy and managed services including systems maintenance, cloud computing, data backup and disaster recovery, VoIP, web hosting, and network security support. Also offers software…
Serves SMEs and large enterprises needing outsourced IT support and security expertise, with emphasis on local small businesses that lack an in-house IT department.
Financial Health
StableStable · Hiring · 6% CAGR over 4y
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Computed from 3 filingsDevelops digital security and identity verification technology that enables organisations to prove credentials, permissions and compliance using cryptographic proofs without exposing underlying data,…
Serves B2B organisations managing regulated workforces, supplier networks or asset inventories, including operations, compliance, security and onboarding teams across value chains.
Financial Health
WeakWeak · Hiring · 134% CAGR over 2y
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Computed from 2 filingsDevelops software for telecommunications and mobile money providers including fraud management, revenue assurance, credit risk and anti‑money laundering systems. Also provides data integration,…
Sells to businesses, particularly communication service providers and mobile money service providers, seeking fraud prevention, revenue assurance, risk management and data integration solutions.…
Financial Health
StableStable · -25% CAGR over 1y
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How Reading Cybersecurity companies work and how to sell to them
What they do
Reading cyber security firms usually make money from a mix of recurring protection work and project-based assurance. Managed service contracts bundle monitoring, alert triage, vulnerability management and reporting into monthly or annual fees, while testing and incident-preparedness work is scoped around defined systems, audits or board deadlines. Software-led suppliers tend to price by users, endpoints, workloads, events or protected applications, with services attached for deployment and tuning. Gross margin depends on how much analyst time sits behind the promise: a tool-only subscription scales differently from a retainer that includes out-of-hours response, evidence packs and senior security judgement.
Who they sell to
Typical buyers are security leaders, heads of infrastructure, risk owners and procurement teams inside mid-market and enterprise organisations, with public-sector routes where framework access and assurance evidence matter. The technical evaluator may be a chief information security officer or senior engineer; the budget holder may sit with the chief information officer, chief operating officer or risk committee. Deals are usually direct-sales led, supported by technical workshops, questionnaires and proof-of-competence checks. Smaller engagements can close after a scoped assessment, but recurring protection contracts tend to move through supplier due diligence, data-processing review and commercial negotiation before signature.
What they buy
Most cyber security suppliers tend to spend on the same operating stack they help clients scrutinise: cloud hosting, secure development tooling, ticketing, case management, endpoint protection, identity controls, logging, threat-intelligence feeds and evidence management. Service-heavy firms also buy professional indemnity cover, legal advice, finance support, training, accreditations, recruitment and contractor capacity for specialist testing or response work. Commercial teams need CRM, proposal tooling, partner management, marketing operations and customer success systems, but buying appetite is usually filtered through client confidentiality, access controls and audit trails. Vendors that cannot explain data location, permissions and operational resilience will struggle.
Why and how to sell to them
Cybersecurity buyers tend to review suppliers when client demand stretches analyst capacity, a new managed-service line is launched, a senior security hire joins, or tender requirements become harder to evidence. Funding, acquisition interest, accreditation work and movement into public-sector or essential-service accounts can also create buying windows. Outbound messages land better when they are tied to a specific operational friction: reducing manual reporting, shortening triage time, proving GDPR or NIS controls, separating client environments, or improving utilisation across consultants. Claims need to survive technical scrutiny; vague risk reduction language is less useful than a clear account of workflow, evidence and implementation effort.
How this list is built
Data sources
This list is built from UK Companies House filings, XBRL accounts data, and semantic analysis of each company's public website. Revenue and headcount figures come from the most recent filed accounts; where the company has not filed, values are estimated using a model trained on filed history and peer benchmarks and are labelled as estimates.
Classification
Rather than relying solely on SIC codes, Firmbase classifies each company semantically: the company's website is crawled, an AI model reads what the company actually sells, and the company is placed into the relevant industry and subsectors. SIC codes are used as one signal but not the only one. This means a company that registered under a generic SIC code but pivoted into (for example) fintech is correctly identified as fintech, not as its original SIC category.
Freshness
The underlying company data is refreshed from Companies House continuously; filings appear in the list within days of submission. The curated list ordering is regenerated when the underlying data moves meaningfully (company count changes by more than 5%, a new company enters the top-ranked segment, or the filed-revenue numbers for the top firms change). You can see the last-updated timestamp near the top of the page.
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