SSP and exchange
Xandr (Microsoft)
appnexus.com
appnexus.com is the domain of the exchange that began as AppNexus, became Xandr and is now part of Microsoft Advertising.
Most of the 212,876 apps that declare appnexus.com reach it through a reseller: 100% have a RESELLER line, 26% a DIRECT one (34,687 files, 20,997 of them through conversantmedia.com's account). 34% of the 1,328,040 lines checked name an account its sellers.json (1,485 sellers) does not list. 25 sellers left its sellers.json in the last 30 days.
- Apps declaring it
- 212,876
- Sellers in sellers.json
- 1,485
- Lines verified
- 41%
- Lines with errors
- 484,189
- Avg. supply path score
- 51.8 / 100
54,526 DIRECT · 212,387 RESELLER
0.9% confidential
551,920 of 1,338,476 checked lines
1,338,476 lines in total
209,292 apps scored
App counts, the sellers.json breakdown and the directory ranking are as of , recomputed daily (the same numbers as the directory). Line counts are recounted every 10 minutes. sellers.json last read 14 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 Xandr (Microsoft) 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.
appnexus.com, YOUR_ACCOUNT_ID, DIRECT, f5ab79cb980f11d1
appnexus.com, YOUR_ACCOUNT_ID, RESELLER, f5ab79cb980f11d1- Field 1:
appnexus.com, the domain Xandr (Microsoft) uses in app-ads.txt. - Field 2: your account ID with Xandr (Microsoft). It must equal the
seller_idin Xandr (Microsoft)'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):
f5ab79cb980f11d1, the certification authority ID on 76% of the lines naming appnexus.com.
sellers.json at a glance
- Status
- Published
- Sellers listed
- 1,485
- Confidential
- 13 (0.9%)
- Passthrough
- 0
- Removed, last 30 days
- 25
- Last read
- Oct 14, 2026
- PUBLISHER939
- INTERMEDIARY325
- BOTH221
Cross-check of lines naming appnexus.com
- Verified 551,920
- Seller ID not found 457,831
- DIRECT but intermediary 6,781
- RESELLER but publisher 19,577
- Seller type BOTH 302,364
- Confidential seller 3
- No sellers.json 0
- Unchecked 0
Every line naming appnexus.com is looked up in its sellers.json. What each status means
Common errors with appnexus.com lines
-
Seller ID not found
457,831 lines
Ask Xandr (Microsoft) 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.
-
Seller type BOTH
302,364 lines
The account is listed as BOTH, so sellers.json alone cannot tell a buyer which relationship applies. Nothing to fix on your side; buyers usually look at the seller's domain.
-
RESELLER but publisher
19,577 lines
If the account is yours, declare it DIRECT. If a partner holds it, ask Xandr (Microsoft) why the account is listed as PUBLISHER.
-
DIRECT but intermediary
6,781 lines
If a partner holds this account and resells your inventory, the line should say RESELLER. If the account is yours, ask Xandr (Microsoft) to list it as PUBLISHER.
-
Confidential seller
3 lines
The seller is confidential in sellers.json: its name and domain are hidden, so buyers cannot confirm who it is.
Intermediaries most declared as RESELLER
Accounts on appnexus.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 |
|---|---|---|
| conversantmedia.com | BOTH | 20,997 |
| outbrain.com | INTERMEDIARY | 20,278 |
| bidmachine.io | INTERMEDIARY | 19,247 |
| thebrave.io | BOTH | 19,146 |
| 152media.info | BOTH | 18,204 |
| admanmedia.com | INTERMEDIARY | 17,833 |
| smartadserver.com | INTERMEDIARY | 17,450 |
| algorix.co | INTERMEDIARY | 17,100 |
Apps that declare appnexus.com
| App | Store | Relationship | Status |
|---|---|---|---|
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | DIRECT | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| iOS | DIRECT | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | DIRECT + RESELLER | Live |
Questions about Xandr (Microsoft)
Does Xandr (Microsoft) publish a sellers.json?
Yes. Its file at https://acdn.adnxs.com/sellers/1d/appnexus/sellers.json listed 1,485 sellers when we last read it on 14 October 2026: 939 publishers, 325 intermediaries and 221 listed as both; 0.9% are confidential.
How many apps declare Xandr (Microsoft) in app-ads.txt?
212,876 apps in Stoqlab's data (delisted apps included) declare appnexus.com: 54,526 with at least one DIRECT line and 212,387 with at least one RESELLER line, across 34,687 app-ads.txt files, as of 14 October 2026 (recounted daily).
What is the certification authority ID for Xandr (Microsoft)?
76% of the app-ads.txt lines naming appnexus.com carry "f5ab79cb980f11d1" 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 appnexus.com lines fail verification?
Of 1,338,476 lines naming appnexus.com, 484,189 contradict its sellers.json. The most common case is "Seller ID not found", on 457,831 lines. Ask Xandr (Microsoft) 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.
Not sure whether your line should say DIRECT or RESELLER? DIRECT vs RESELLER in app-ads.txt
Sources: the public app-ads.txt files of tracked apps and the sellers.json of appnexus.com. Something wrong? Tell us.