From The Accountability Gap, an audit of the open ad-supply record
A Catalog of Departed Ad-Exchanges, still listed by the living.
Twelve specimens of Supply-Side Platforms which have been acquired, rebranded, or wound up — yet remain declared in 287,249 DIRECT claims across 25,239 publishers'ads.txt files at the time of pressing. Each entry's persistence is measured in years.
The Accountability Gap · Edition VIII · Snapshot 22·V·MMXXVI · CC0
Praefatio
The framework provides no channel for deregistration.
When an exchange is acquired, rebranded, or goes bankrupt, no propagation occurs through the ads.txt standard. The publisher's file is not notified. The wrapper template is not updated. The IAB Tech Lab maintains no registry of the deceased. The result, set down below in the manner of a natural-history catalog, is the half-life of an exchange's name in the public record after it has ceased to operate. The reader will note that some names persist nine years post-acquisition. This is not fraud. It is decay.
Cat. № 001I
rhythmone .com
MMXIV — MMXIX acta est fabula
RhythmOne
Tremor-acquisita, anno MMXIX
years departed7
still carried by14,973 publishers
% of corpus20.18%
Acquired by Tremor International. The merged entity has been operating as Nexxen since 2024. One in five publishers still names rhythmone.com as a DIRECT seller.
Cat. № 002II
emxdgt .com
MMXVI — MMXXIII requiescat
EMX Digital
Big Village (banca rupta), anno MMXXIII
years departed3
still carried by13,544 publishers
% of corpus18.25%
Big Village (the parent company) filed for Chapter 7 bankruptcy. The exchange ceased operations. The name has not been removed from the public record.
Cat. № 003III
advertising .com
MCMXCVIII — MMXVII aurum reliquum
Advertising.com
Yahoo legati reliquum, anno MMXVII
years departed9
still carried by9,384 publishers
% of corpus12.65%
An original AOL property folded into Yahoo's legacy stack in 2017. Nine years past its operational end, it remains the third most ubiquitous DIRECT-claimed ghost.
Cat. № 004IV
districtm .io
MMXII — MMXXI absorptum
districtm
Magnite-acquisita, anno MMXXI
years departed5
still carried by9,407 publishers
% of corpus12.68%
Acquired by Magnite. Existing publishers should declare rubiconproject.com instead. They have not.
Cat. № 005V
spotx .tv
MMVII — MMXXII absorptum
SpotX
Magnite-acquisita, anno MMXXII
years departed4
still carried by7,858 publishers
% of corpus10.55%
A specialist video exchange consolidated into Magnite. Persists in the public record alongside its successor.
Cat. № 006VI
aolcloud .net
MMV — MMXVII aurum reliquum
AolCloud
Yahoo legati reliquum, anno MMXVII
years departed9
still carried by7,046 publishers
% of corpus9.49%
An AOL infrastructure name absorbed into Yahoo in 2017. Still cited as a DIRECT seller in nearly one in ten audited ads.txt files.
Cat. № 007VII
vi .ai
MMXV — MMXXI renominatum
Vi.ai
renominatum, anno MMXXI
years departed5
still carried by7,868 publishers
% of corpus10.60%
Discontinued under its old name when the parent entity rebranded. The replacement domain is unknown to most of the publishers still declaring it.
Cat. № 008VIII
admixer .net
MMVIII — MMXX renominatum
AdMixer
renominatum, anno MMXX
years departed6
still carried by5,754 publishers
% of corpus7.75%
Operates today as a different entity at a different domain. The ads.txt files have not followed.
Cat. № 009IX
tremorhub .com
MMXIV — MMXIX renominatum
Tremor Hub
renominatum, anno MMXIX
years departed7
still carried by3,876 publishers
% of corpus5.22%
Renamed under a parent's rebrand. Listed alongside the very company that absorbed it.
Cat. № 010X
yieldlab .net
MMVIII — MMXXIII requiescat
Yieldlab
Virtual Minds (decopulata), anno MMXXIII
years departed3
still carried by3,812 publishers
% of corpus5.14%
A German programmatic platform whose parent (Virtual Minds) folded operations.
Cat. № 011XI
aerserv .com
MMXII — MMXVIII absorptum
AerServ
InMobi-acquisita, anno MMXVIII
years departed8
still carried by~3,200 publishers
% of corpus~4.3%
A mobile-video exchange folded into InMobi. Eight years gone, still cited.
Cat. № 012XII
adcolony .com
MMVIII — MMXXI absorptum
AdColony
Digital Turbine-acquisita, anno MMXXI
years departed5
still carried by~3,000 publishers
% of corpus~4.0%
Acquired by Digital Turbine and folded into its broader stack. The brand persists as a memory in publisher files.
Inscriptio · the half-life of a name
Twelve exchanges, all departed. Twenty-five thousand publishers still declaring them direct sellers of their inventory — for an average five years after each departure.
287,249 dead-SSP DIRECT claims · 33.7% of the audited corpus