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 199,836 apps that declare appnexus.com reach it through a reseller: 100% have a RESELLER line, 26% a DIRECT one (32,808 files, 19,780 of them through conversantmedia.com's account). 34% of the 1,259,591 lines checked name an account its sellers.json (1,485 sellers) does not list. 22 sellers left its sellers.json in the last 30 days.
- Apps declaring it
- 199,836
- Sellers in sellers.json
- 1,485
- Lines verified
- 41%
- Lines with errors
- 476,873
- Avg. supply path score
- 51.8 / 100
51,785 DIRECT · 199,377 RESELLER
0.8% confidential
543,279 of 1,317,908 checked lines
1,317,908 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 13 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
- 12 (0.8%)
- Passthrough
- 0
- Removed, last 30 days
- 22
- Last read
- Oct 13, 2026
- PUBLISHER937
- INTERMEDIARY326
- BOTH222
Cross-check of lines naming appnexus.com
- Verified 543,279
- Seller ID not found 450,914
- DIRECT but intermediary 6,708
- RESELLER but publisher 19,251
- Seller type BOTH 297,753
- 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
450,914 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
297,753 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
19,251 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
6,708 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 | 19,780 |
| outbrain.com | INTERMEDIARY | 19,103 |
| bidmachine.io | INTERMEDIARY | 18,148 |
| thebrave.io | BOTH | 18,031 |
| 152media.info | BOTH | 17,183 |
| admanmedia.com | INTERMEDIARY | 16,810 |
| smartadserver.com | INTERMEDIARY | 16,477 |
| algorix.co | INTERMEDIARY | 16,140 |
Apps that declare appnexus.com
| App | Store | Relationship | Status |
|---|---|---|---|
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| iOS | DIRECT + RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | RESELLER | Live | |
| iOS | RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | RESELLER | Live | |
| Android | DIRECT + RESELLER | Live | |
| Android | 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 13 October 2026: 937 publishers, 326 intermediaries and 222 listed as both; 0.8% are confidential.
How many apps declare Xandr (Microsoft) in app-ads.txt?
199,836 apps in Stoqlab's data (delisted apps included) declare appnexus.com: 51,785 with at least one DIRECT line and 199,377 with at least one RESELLER line, across 32,808 app-ads.txt files, as of 13 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 1,317,908 lines naming appnexus.com, 476,873 contradict its sellers.json. The most common case is "Seller ID not found", on 450,914 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.