Ad system
groundtruth.com
groundtruth.com is the domain an ad system uses in app-ads.txt and ads.txt files. 85,330 apps in our data declare it. Its sellers.json lists 37 sellers.
- Apps declaring it
- 85,330
- Sellers in sellers.json
- 37
- Lines verified
- 2.9%
- Lines with errors
- 10,258
- Avg. supply path score
- 49.0 / 100
33 DIRECT · 85,324 RESELLER
0% confidential
303 of 10,561 checked lines
10,561 lines in total
84,207 apps scored
Apps and lines are recounted every 10 minutes. The sellers.json breakdown and the directory ranking are as of , recomputed daily. sellers.json last read 9 October 2026. The supply path score sums up how short and clean the declared paths are, 0 to 100 (how it is computed).
How to add groundtruth.com to app-ads.txt
One line per account, in the app-ads.txt at the root of the domain your App Store and Google Play listings name as the developer website.
groundtruth.com, YOUR_ACCOUNT_ID, DIRECT, 81cbf0a75a5e0e9a
groundtruth.com, YOUR_ACCOUNT_ID, RESELLER, 81cbf0a75a5e0e9a- Field 1:
groundtruth.com, the domain groundtruth.com uses in app-ads.txt. - Field 2: your account ID with groundtruth.com. It must equal the
seller_idin groundtruth.com's sellers.json. - Field 3: DIRECT if you hold the account, RESELLER if a partner holds it and sells your inventory. DIRECT vs RESELLER
- Field 4 (optional):
81cbf0a75a5e0e9a, the certification authority ID on 100% of the lines naming groundtruth.com.
sellers.json at a glance
- Status
- Published
- Sellers listed
- 37
- Confidential
- 0 (0%)
- Passthrough
- 0
- Removed, last 30 days
- 1
- Last read
- Oct 9, 2026
- PUBLISHER15
- INTERMEDIARY22
- BOTH0
Cross-check of lines naming groundtruth.com
- Verified 303
- Seller ID not found 10,258
- DIRECT but intermediary 0
- RESELLER but publisher 0
- Seller type BOTH 0
- Confidential seller 0
- No sellers.json 0
- Unchecked 0
Every line naming groundtruth.com is looked up in its sellers.json. What each status means
Common errors with groundtruth.com lines
-
Seller ID not found
10,258 lines
Ask groundtruth.com for the account ID it lists for you in its sellers.json, correct the line, or remove it if you no longer work with them. Buyers that check sellers.json drop these paths.
Intermediaries most declared as RESELLER
Accounts on groundtruth.com that its sellers.json lists as INTERMEDIARY or BOTH, by the number of app-ads.txt files declaring them. Confidential sellers are left out.
| Seller domain | Type | Files |
|---|---|---|
| smaato.com | INTERMEDIARY | 287 |
| smartadserver.com | INTERMEDIARY | 3 |
Apps that declare groundtruth.com
| App | Store | Relationship | Status |
|---|---|---|---|
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| iOS | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| iOS | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live |
Questions about groundtruth.com
How do I add groundtruth.com to app-ads.txt?
Add one line for each account groundtruth.com gives you: "groundtruth.com, YOUR_ACCOUNT_ID, DIRECT, 81cbf0a75a5e0e9a". Use DIRECT when you hold the account yourself and RESELLER when a partner holds it and sells your inventory through groundtruth.com. The account ID must be the seller_id groundtruth.com lists for you in its sellers.json; groundtruth.com will give it to you. Put the file at the root of the domain named as your developer website in the App Store and Google Play listings.
Does groundtruth.com publish a sellers.json?
Yes. Its file at https://www.groundtruth.com/sellers.json listed 37 sellers when we last read it on 9 October 2026: 15 publishers, 22 intermediaries and 0 listed as both; 0% are confidential.
How many apps declare groundtruth.com in app-ads.txt?
85,330 apps in Stoqlab's data (delisted apps included) declare groundtruth.com: 33 with at least one DIRECT line and 85,324 with at least one RESELLER line, across 10,247 app-ads.txt files. Counts are recomputed daily.
What is the certification authority ID for groundtruth.com?
100% of the app-ads.txt lines naming groundtruth.com carry "81cbf0a75a5e0e9a" in the fourth field. The field is optional; the IAB Tech Lab ads.txt 1.1 specification says identifiers in sellers.json supersede it, so a missing or different value does not make a line invalid.
Why do groundtruth.com lines fail verification?
Of 10,561 lines naming groundtruth.com, 10,258 contradict its sellers.json. The most common case is "Seller ID not found" (10,258 lines): Ask groundtruth.com for the account ID it lists for you in its sellers.json, correct the line, or remove it if you no longer work with them. Buyers that check sellers.json drop these paths.
What is the difference between DIRECT and RESELLER?
DIRECT means the publisher owns the account; RESELLER means an intermediary sells the inventory on the publisher's behalf. DIRECT lines should match a PUBLISHER entry in the network's sellers.json, RESELLER lines an INTERMEDIARY entry.
Sources: the public app-ads.txt files of tracked apps and the sellers.json of groundtruth.com. Something wrong? Tell us.