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Companies

3,695 companies in the AdTech ecosystem

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Onavo

Defunct

Mobile Analytics / VPN (defunct)

Onavo was a mobile analytics + VPN company acquired by Facebook October 2013 (~$120M). Onavo Protect VPN gave Facebook competitive intelligence on user behavior across other apps — used to inform acquisition strategy (notably WhatsApp). Apple removed Onavo from the App Store August 2018 for violating data-collection policies. Facebook shut down Onavo entirely February 21, 2019 amid privacy backlash and FTC scrutiny.

Onclusive

Onclusive

PR Analytics & Media Intelligence

Onclusive is a global PR analytics and media intelligence platform that helps communications professionals measure earned media impact and demonstrate PR ROI.

Data & AnalyticsMarketing AnalyticsSan Francisco, California
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One Agency

Advertising Agency

Cheil's MENA regional hub, headquartered in Dubai. Serves Samsung-Middle-East plus regional brand work. Slug includes "-uae" suffix to disambiguate from other "One Agency" naming collisions in the global agency landscape. Source: Cheil Sustainability Report 2014.

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One Identity

Identity & Access Management / AdTech Identity

One Identity — recorded in ATDb as the acquirer/parent of one or more AdTech companies (s375 lineage backfill).

Aliso Viejo, California
OneLogin

OneLogin

Acquired

Identity and Access Management (IAM)

OneLogin is a cloud-based identity and access management (IAM) platform that provides single sign-on, multi-factor authentication, and user provisioning for enterprises.

Identity ResolutionPrivacy TechnologySan Francisco, California
OneSignal

OneSignal

Customer Engagement / Marketing Technology

OneSignal is a leading customer engagement platform that enables businesses to send targeted push notifications, in-app messages, email, and SMS. It helps developers and marketers engage their users across multiple channels to improve retention and drive growth for their applications and websites.

Marketing AutomationCustomer EngagementSan Mateo, California
OneTag

OneTag

Publisher Monetization & Header Bidding

Header bidding and yield optimization platform for publishers, offering wrapper solutions and programmatic monetization tools. Provides advanced header bidding technology to maximize publisher revenue.

Supply Side Platform (SSP)Paris, Île-de-France
OneTrust

OneTrust

Privacy Tech / Consent Management

OneTrust is a leading privacy, security, and data governance software platform that helps organizations manage compliance with global privacy regulations including GDPR, CCPA, and cookie consent.

Privacy & Consent ManagementPrivacy TechnologyAtlanta, Georgia
OneView

OneView

Rebranded

Connected TV / Programmatic Advertising

OneView is a programmatic advertising technology platform specializing in converged TV advertising solutions that bridge traditional linear television and modern digital streaming environments. The company addresses the critical challenge of audience fragmentation across cable, satellite, over-the-air broadcast, and multiple streaming services by providing unified programmatic access to both legacy broadcast inventory and connected TV (CTV) placements through a single integrated platform. Thi...

CTV PlatformVerification & MeasurementSan Jose, California
Onfido

Onfido

Acquired

Identity Verification & Fraud Prevention

Onfido is an AI-powered identity verification and authentication platform that helps businesses verify real user identities using document checks and biometric analysis — now part of Entrust following a 2024 acquisition.

Identity ResolutionVerification PlatformLondon, England
Ontology

Ontology

Blockchain Infrastructure / Decentralized Identity / Enterprise Web3

Ontology is a high-performance public blockchain infrastructure provider that specializes in decentralized identity solutions and secure data management for enterprise applications. Operating as a dual-token blockchain network utilizing ONT and ONG tokens, the platform combines distributed ledger technology with digital identity verification systems to create comprehensive trust frameworks for organizations across financial services, healthcare, government, and enterprise sectors. Ontology's ...

Identity ResolutionBlockchain Advertising
Ontraport

Ontraport

Marketing Automation & CRM

Ontraport is a comprehensive business automation platform that combines customer relationship management (CRM), marketing automation, and e-commerce capabilities into a unified solution. The platform is designed to help small to medium-sized businesses streamline their operations by automating repetitive tasks, managing customer relationships, and executing sophisticated marketing campaigns without requiring extensive technical expertise. Ontraport serves entrepreneurs, digital marketers, and...

Marketing PlatformMarketing AutomationSanta Barbara, California
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Oodle

Classified Advertising Technology

Oodle is a classified advertising platform and technology provider that aggregates listings from various sources and distributes them across partner networks.

Marketplace TechnologySan Mateo, California
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oolo

Acquired

Mobile User Acquisition & Monetization Optimization

AI-powered UA & monetization platform acquired by AppsFlyer December 5 2023 (all-stock).

AI-Powered PlatformMarketing AutomationTel Aviv, Tel Aviv District
Ooyala

Ooyala

Acquired

Video Technology / AdTech

Ooyala was a video technology platform that provided online video publishing, analytics, and monetization solutions before being acquired and eventually shut down.

Video TechnologySanta Clara, California
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Open Bidding

Server-side Header Bidding

Google's server-side header-bidding product within Google Ad Manager, formerly known as Exchange Bidding (or Exchange Bidding in Dynamic Allocation, EBDA). Allows third-party SSPs/exchanges to compete with Authorized Buyers in real-time auctions. The Trade Desk publicly exited Open Bidding April 2025, citing GAM transparency concerns — a notable industry signal favoring Prebid + alternatives. Distinct from header bidding (client-side); Open Bidding is server-side via GAM.

Open Web Analytics

Open Web Analytics

Web Analytics & Business Intelligence

Open Web Analytics is an open-source web analytics platform that provides organizations with complete control over their website visitor data while delivering comprehensive insights into user behavior and engagement. As a self-hosted alternative to proprietary analytics solutions like Google Analytics, the platform offers extensive tracking capabilities including page views, event monitoring, e-commerce transaction analysis, and detailed visitor profiling—all while ensuring data sovereignty...

Data & AnalyticsMarketing Analytics
OpenAds

OpenAds

Programmatic Advertising / Publisher Monetization

The Trade Desk's sell-side prebid wrapper / publisher auction platform. Launched October 2 2025 with first-wave publisher partners (AccuWeather, BuzzFeed, Hearst, Guardian, Ziff Davis). Forks Prebid code with mandatory TID sharing; integrates with OpenPath. Major strategic move into the sell-side — distinct from OpenPath (which is supply-path optimization for buyers).

Supply Side Platform (SSP)Programmatic PlatformVentura, California
OpenAI

OpenAI

AI / Generative AI Infrastructure for AdTech & MarTech

OpenAI is the creator of ChatGPT and the GPT series of large language models, providing cutting-edge AI APIs and tools that are rapidly transforming advertising, content creation, and marketing technology.

Creative PlatformAI-Powered PlatformSan Francisco, California
OpenInfluence

OpenInfluence

Influencer Marketing

OpenInfluence is a global influencer marketing company that connects brands with relevant creators to execute data-driven campaigns. They leverage proprietary technology and a vast network of influencers to deliver measurable results across various social media platforms, helping brands achieve their marketing objectives.

Influencer MarketingMarketing AgencyLos Angeles, California
OpenPath

OpenPath

Direct Publisher Supply Path

OpenPath is The Trade Desk's direct supply path to publishers via Prebid, launched February 2022. Bypasses traditional SSPs in some integrations to give TTD direct access to publisher inventory. Has had publisher pull-back in 2025 amid auction-quality concerns.

Supply Side Platform (SSP)
OpenRTB Consortium

OpenRTB Consortium

Programmatic Advertising Standards

Industry consortium that develops and maintains the OpenRTB protocol, the standard specification for real-time bidding in programmatic advertising.

Programmatic PlatformNew York, New York
OpenSlate

OpenSlate

Brand Safety and Contextual Intelligence

OpenSlate is a leading provider of brand safety and suitability solutions for digital advertising. The company's platform analyzes and classifies online content to help brands and agencies ensure their ads are placed in brand-safe and suitable environments.

Contextual AdvertisingAd Fraud PreventionNew York, New York
OpenWeb

OpenWeb

Publisher Technology / Audience Engagement & Monetization

Audience-engagement and conversation platform with an advertising business.

New York, New York