Lesson 5 of 5 · 8 min read · advanced
Who owns who in ad tech
A readable ownership map of ad tech: the tech giants, media and telecom owners, agency holding companies, independents and private equity.
When you buy an ad, the software you use, the exchange that runs the auction and the company that measures the result may all belong to the same parent, or to fierce rivals. Knowing who owns what helps you spot conflicts of interest, understand why products get shut down or merged, and read industry news without getting lost.
It is like a shopping street where many shop signs look independent, but half the shops belong to three families. You may think you are comparing prices across competitors when you are really choosing between cousins.
The big tech owners
| Parent | Key ad tech assets | What it means |
|---|---|---|
| Alphabet (Google) | Google Ad Manager (the former DoubleClick publisher ad server plus the AdX exchange), Google Ads, Display & Video 360, Campaign Manager 360 | Owns tools on the buy side, the sell side and the exchange in between; the subject of US and EU antitrust rulings. |
| Microsoft | Microsoft Advertising, Xandr assets (bought from AT&T in 2022), Monetize and Curate | Announced its Invest DSP would close by February 2026; focus shifting to sell-side, curation and Copilot-era ads. |
| Amazon | Amazon Ads, Amazon DSP, Prime Video ads, Twitch | A retailer that is also a major DSP and CTV seller, with shopping data others lack. |
| Meta | Facebook, Instagram, WhatsApp ad products, Audience Network | A walled garden: buying, inventory and measurement mostly inside one company. |
Media and telecom owners
Comcast owns FreeWheel, a leading video and CTV ad-serving platform used by many TV networks, which it bought in 2014. Media owners buy ad tech so they can sell their own streaming inventory efficiently. Telecom companies have moved in and out: AT&T bought AppNexus in 2018 to form Xandr, then sold Xandr to Microsoft. That churn is a reminder that ad tech ownership often follows the parent’s wider strategy rather than the product’s success.
Agency holding companies
Most big brands buy media through agencies owned by a handful of holding companies. After Omnicom completed its acquisition of Interpublic in November 2025, the largest groups are Omnicom, WPP (UK), Publicis Groupe (France), Dentsu (Japan) and Havas (France). Several own ad tech and data assets: Publicis owns Epsilon, a data and marketing company, and Omnicom owns the Acxiom data business it gained with IPG. Holdcos also run trading desks and principal-buying units, which is why they appear in debates about transparency.
Independent listed companies
- The Trade Desk: the largest independent DSP, positioning itself as the buy-side alternative to walled gardens.
- Magnite and PubMatic: independent SSPs serving web, app and CTV publishers.
- DoubleVerify: listed verification company, which has acquired Scibids and Rockerbox.
- Criteo: French-founded company focused on commerce and retail media.
- Teads: the renamed Outbrain after it bought Teads from Altice in 2025.
- Taboola: content recommendation and performance advertising.
- Unity and AppLovin: game engines and app-monetisation platforms that are among the biggest players in mobile in-app advertising.
Private equity owners
Private equity firms buy ad tech businesses with steady cash flow and aim to grow or merge them before selling. Two examples you will often hear: Vista Equity Partners took a majority stake in the SSP TripleLift in 2021 in a deal valued at more than $1.4 billion, and Novacap, a Canadian firm, bought Integral Ad Science for $1.9 billion in a take-private completed in December 2025. Before its 2021 stock market listing, IAS was itself controlled by Vista, so the same company can pass through several owners in a decade.
| Owner type | Examples | Typical motive | What to watch |
|---|---|---|---|
| Big tech | Google, Microsoft, Amazon, Meta | Monetise owned inventory and data at huge scale | Self-preferencing, data advantages |
| Media / telecom | Comcast (FreeWheel) | Sell own TV and streaming inventory | Product priorities follow the parent |
| Agency holdco | Omnicom, WPP, Publicis, Dentsu, Havas | Capture more of the client budget | Principal buying, rebates |
| Independent listed | The Trade Desk, Magnite, PubMatic, DoubleVerify | Grow as neutral alternatives | Quarterly pressure, take-rate squeeze |
| Private equity | Vista (TripleLift), Novacap (IAS) | Improve, merge, sell within years | Cost cuts, bolt-on deals, eventual resale |
The pattern behind all of this is simple. Whoever controls the most inventory, the most data or the most client budgets tends to buy the tools that sit next to them. Independents survive by being neutral, and neutrality is a selling point only as long as the giants are seen to favour themselves. That is why ownership, competition law and industry standards are so closely linked.
Key takeaways
- Big tech owners such as Google, Amazon, Meta and Microsoft control inventory, data and tools across several layers.
- Agency holding companies, now led by Omnicom after its IPG deal, own data and trading assets as well as agencies.
- Independents such as The Trade Desk, Magnite and PubMatic sell neutrality as their advantage.
- Private equity firms such as Vista (TripleLift) and Novacap (IAS) are major owners, and ownership changes often.
Questions people ask
Who owns Xandr now?
Microsoft bought Xandr, formerly AppNexus, from AT&T in a deal completed in 2022 and folded it into Microsoft Advertising. In 2025 Microsoft announced it would shut down the Invest DSP, Xandr’s buy-side platform, by the end of February 2026, while continuing sell-side and curation products such as Microsoft Monetize and Microsoft Curate.
Who owns Integral Ad Science (IAS)?
Integral Ad Science is owned by Novacap, a Canadian private equity firm, which completed its $1.9 billion all-cash acquisition on 23 December 2025. IAS shareholders received $10.30 per share and the company’s stock stopped trading on Nasdaq. Before its 2021 initial public offering, IAS had been controlled by Vista Equity Partners.
What are the biggest advertising holding companies?
After Omnicom completed its purchase of Interpublic Group in November 2025, the largest agency holding companies are Omnicom, WPP, Publicis Groupe, Dentsu and Havas. They own creative and media agencies around the world and, increasingly, data, commerce and technology businesses such as Epsilon at Publicis and Acxiom at Omnicom.