ads.txt vs app-ads.txt vs sellers.json: three files, three jobs

ads.txt vs app-ads.txt vs sellers.json: three files, three jobs
Confirmed: people treat these as one chore and ship gaps that crater CTV/app revenue.
— ads.txt: declares who can sell YOUR web inventory. Web only.
— app-ads.txt: same job for apps — but buyers fetch it from the developer URL in the store listing, not your domain. Misconfigured store URL = invisible.
— sellers.json: the SSP's published list of who THEY represent. The buy-side cross-checks all three.
Impact: If your app store 'developer website' field is wrong, app-ads.txt never resolves and CTV demand evaporates. (confirmed)