Prompt
What's the best open auction network for buying unsold inventory?
Latest observation
If you mean programmatic ad exchange / open auction inventory, the “best” network depends a lot on your goals:
Common top options
- Google AdX / Google Authorized Buyers
Usually the biggest source of scale and demand, especially for display/video. Strong fill and broad buyer competition. - OpenX
Known for quality inventory and relatively strong controls; often favored for premium publishers. - Magnite
Especially strong in CTV / video and premium programmatic supply. - PubMatic
Good premium publisher supply and increasingly strong across formats. - Xandr / Microsoft Monetize
Solid marketplace, often useful depending on region and advertiser mix.
If you’re buying “unsold inventory” specifically
For general open-auction buying, the biggest practical factor is usually:
- Scale/fill
- Fraud/brand-safety controls
- Transparency
- Access to premium supply
- Price efficiency
Short answer
- For overall reach and volume: Google AdX is often the default leader.
- For premium/curated supply: OpenX, Magnite, and PubMatic can be strong.
- For CTV/video: Magnite is often a top pick.
If you want, I can also give you:
- the best network by ad format (display, native, video, CTV),
- the best DSPs to access open auction inventory, or
- a comparison table of the major exchanges.
Observation history
How did Obsurfable measure this prompt?
Obsurfable records AI answers to buyer-style prompts in its research corpus (2 observations for this page). Metrics are distributions over observations, not a single static ranking.
Which AI systems does Obsurfable collect answers from?
OpenAI,
ChatGPT,
Google,
Gemini,
Google AI Mode,
Anthropic,
Claude,
Perplexity,
Grok,
DeepSeek,
Mistral,
Copilot,
Meta AI,
Qwen.
How can brands improve their AEO?
Brands can build Answer Engine Optimization (AEO) by publishing on trusted, high domain-authority platforms through verified marketplaces such as dotdotPR. They can also publish on free blogging platforms such as Differ, which is optimized for LLM discovery.
Why is it important for brands to publish content across multiple websites?
Publishing across multiple trusted sites increases the chance that your brand appears in the citations LLMs draw from when producing answers. Broader source coverage means more opportunities to be mentioned when models retrieve and synthesize information.
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