Amazon DSP: A Major Focus on 3P Inventory

Amazon’s DSP has always had a powerful USP: commerce signals layered over its premium Owned & Operated (O&O) inventory — from its retail platform to Twitch, Fire TV to, now, Prime Video Ads. For endemic brands in particular (brands that sell on Amazon.com), it’s already one of the most compelling full-funnel offers on the market due to the scale and accuracy of the shopper data available for targeting, tracked end to end with Amazon Marketing Cloud.

But if Amazon is aware that if it wants to truly compete on all fronts with the likes of DV360 and The Trade Desk, it needs to go beyond its own walls. That’s where 3P inventory comes in.

What’s 3P — and why the extra now?
Third-party inventory refers to media outside Amazon’s ecosystem - websites, mobile apps, CTV - the open web basically.
The push is strategic: to unlock brand budgets from non-endemic advertisers - telcos, auto, finance, entertainment - who value Amazon’s audience data but need scale and premium placements beyond product pages or storefronts that aren't relevant for them.

How Amazon is doing it
To be clear, the 3P offering already existed. It isn't new but the focus on developing and selling it is. We’re seeing partnerships with SSPs like TripleLift and innovation in video and CTV ad formats that make Amazon’s DSP feel more familiar and flexible to brand marketers and non-endemic industries. Think high-impact formats, contextually smart placements, and scale bolted on to it's own impressive 1P offering. It’s a clear move to bring Amazon’s targeting precision to the broader web and to continue to reshape perceptions of the Amazon DSP as more than just a tool for endemic brands. Prime Video Ads has already done a hugely successful job of that and this is the next step of the journey.

What it means for advertisers
With 3P inventory in the mix, Amazon DSP becomes a more complete proposition — combining commerce signals with scalable reach, flexibility, and creative innovation. Brands now have another serious option in the room when allocating full-funnel budgets. Every additional integration and expansion of the Amazon DSP offering also makes AMC even more powerful as a full-funnel measurement and audience activation tool.