<s>
Apple	O
's	O
Identifier	B-Operating_System
for	I-Operating_System
Advertisers	I-Operating_System
(	O
IDFA	O
)	O
is	O
a	O
unique	O
random	O
device	O
identifier	O
Apple	O
generates	O
and	O
assigns	O
to	O
every	O
device	O
.	O
</s>
<s>
It	O
is	O
intended	O
to	O
be	O
used	O
by	O
advertisers	O
to	O
deliver	O
personalized	O
ads	O
and	O
attribute	O
ad	O
interactions	O
for	O
ad	B-Protocol
retargeting	I-Protocol
.	O
</s>
<s>
Starting	O
in	O
iOS	B-Operating_System
14.5	I-Operating_System
,	O
iPadOS	O
14.5	O
,	O
and	O
tvOS	O
14.5	O
,	O
users	O
are	O
prompted	O
to	O
decide	O
whether	O
to	O
opt-in	O
or	O
out	O
of	O
IDFA	O
sharing	O
before	O
apps	O
can	O
query	O
it	O
.	O
</s>
<s>
In	O
May	O
,	O
2021	O
,	O
Verizon-owned	O
advertisement	O
analytics	O
company	O
Flurry	B-Application
Analytics	O
reported	O
that	O
96%	O
of	O
US	O
users	O
opted	O
out	O
of	O
IDFA	O
sharing	O
.	O
</s>
<s>
Since	O
January	O
2021	O
,	O
users	O
and	O
developers	O
could	O
test	O
this	O
change	O
by	O
installing	O
iOS	B-Operating_System
14	I-Operating_System
beta	O
release	O
.	O
</s>
<s>
In	O
July	O
2020	O
,	O
Facebook	B-Application
stated	O
that	O
this	O
transparency	O
requirement	O
would	O
likely	O
hurt	O
their	O
advertising	O
targeting	O
.	O
</s>
<s>
Facebook	B-Application
said	O
that	O
these	O
changes	O
"	O
may	O
render	O
[	O
their	O
tracking ]	O
so	O
ineffective	O
on	O
iOS	B-Operating_System
14	I-Operating_System
that	O
it	O
may	O
not	O
make	O
sense	O
to	O
offer	O
it	O
on	O
iOS	B-Operating_System
14	I-Operating_System
"	O
and	O
Facebook	B-Application
apps	O
on	O
iOS	B-Operating_System
14	I-Operating_System
,	O
including	O
Facebook	B-Application
,	O
WhatsApp	B-Application
,	O
Instagram	B-Application
,	O
Messenger	B-Protocol
,	O
and	O
others	O
will	O
not	O
collect	O
IDFA	O
on	O
iOS	B-Operating_System
14	I-Operating_System
.	O
</s>
<s>
In	O
December	O
2020	O
,	O
the	B-Operating_System
Mozilla	I-Operating_System
Foundation	I-Operating_System
expressed	O
support	O
for	O
Apple	O
restricting	O
access	O
to	O
IDFA	O
and	O
asked	O
users	O
to	O
sign	O
a	O
petition	O
to	O
"	O
help	O
strengthen	O
 [ Apple's ] 	O
resolve	O
to	O
protect	O
consumer	O
privacy	O
"	O
.	O
</s>
<s>
On	O
December	O
15	O
,	O
2020	O
,	O
Facebook	B-Application
launched	O
a	O
"	O
Speak	O
Up	O
for	O
Small	O
Businesses	O
"	O
campaign	O
against	O
Apple	O
.	O
</s>
<s>
In	O
this	O
campaign	O
,	O
Facebook	B-Application
purchased	O
full-page	O
advertisements	O
in	O
newspapers	O
and	O
created	O
a	O
web	O
page	O
claiming	O
Facebook	B-Application
tries	O
to	O
help	O
small	O
businesses	O
.	O
</s>
<s>
This	O
campaign	O
became	O
controversial	O
even	O
within	O
Facebook	B-Application
itself	O
,	O
because	O
some	O
employees	O
thought	O
Facebook	B-Application
was	O
"	O
trying	O
to	O
justify	O
doing	O
a	O
bad	O
thing	O
by	O
hiding	O
behind	O
people	O
with	O
a	O
sympathetic	O
message.	O
"	O
</s>
<s>
On	O
January	O
27	O
,	O
2021	O
,	O
Google	B-Application
announced	O
that	O
when	O
the	O
new	O
requirement	O
goes	O
into	O
effect	O
,	O
a	O
"	O
handful	O
"	O
of	O
Google	B-Application
apps	O
will	O
stop	O
collecting	O
IDFAs	O
(	O
and	O
thus	O
the	O
apps	O
will	O
avoid	O
displaying	O
a	O
prompt	O
for	O
allowing	O
tracking	O
user	O
activity	O
)	O
.	O
</s>
<s>
In	O
February	O
2021	O
,	O
Post-IDFA	O
alliance	O
surveyed	O
600	O
customers	O
and	O
noted	O
that	O
38.5	O
%	O
of	O
them	O
said	O
they	O
plan	O
to	O
allow	O
tracking	O
by	O
tapping	O
"	O
yes	O
"	O
in	O
the	O
App	B-Operating_System
Tracking	I-Operating_System
Transparency	I-Operating_System
prompt	O
.	O
</s>
<s>
On	O
March	O
18	O
,	O
2021	O
,	O
Facebook	B-Application
changed	O
its	O
stance	O
.	O
</s>
<s>
Facebook	B-Application
CEO	O
,	O
Mark	O
Zuckerberg	O
,	O
claimed	O
that	O
these	O
changes	O
might	O
even	O
strengthen	O
Facebook	B-Application
's	O
position	O
"	O
if	O
Apple	O
’s	O
changes	O
encourage	O
more	O
businesses	O
to	O
conduct	O
more	O
commerce	O
on	O
 [ Facebook's ] 	O
platforms	O
by	O
making	O
it	O
harder	O
for	O
them	O
to	O
use	O
their	O
data	O
in	O
order	O
to	O
find	O
the	O
customers	O
that	O
would	O
want	O
to	O
use	O
their	O
products	O
outside	O
of	O
 [ Facebook's ] 	O
platforms	O
"	O
.	O
</s>
<s>
On	O
April	O
1	O
,	O
2021	O
,	O
the	O
Apple	O
App	O
Store	O
started	O
rejecting	O
apps	O
which	O
used	O
Adjust	O
SDK	O
and	O
attempted	O
to	O
circumvent	O
App	B-Operating_System
Tracking	I-Operating_System
Transparency	I-Operating_System
rules	O
via	O
device	B-Protocol
fingerprinting	I-Protocol
(	O
collecting	O
device	O
and	O
usage	O
data	O
to	O
create	O
a	O
unique	O
identifier	O
in	O
order	O
to	O
track	O
the	O
user	O
)	O
.	O
</s>
<s>
In	O
May	O
,	O
2021	O
,	O
Verizon-owned	O
advertisement	O
analytics	O
company	O
Flurry	B-Application
reported	O
that	O
96%	O
of	O
US	O
users	O
opted	O
out	O
of	O
IDFA	O
sharing	O
.	O
</s>
<s>
Apple	O
unconditionally	O
disables	O
Apple	B-Operating_System
IDFA	I-Operating_System
sharing	O
for	O
some	O
Apple	B-General_Concept
ID	I-General_Concept
accounts	O
.	O
</s>
<s>
Restrictions	O
apply	O
if	O
the	O
Apple	B-General_Concept
ID	I-General_Concept
is	O
:	O
</s>
<s>
In	O
March	O
2021	O
,	O
the	O
China	O
Advertising	O
Association	O
announced	O
that	O
it	O
was	O
backing	O
a	O
device	B-Protocol
fingerprinting	I-Protocol
system	O
as	O
a	O
work-around	O
for	O
Apple	O
's	O
new	O
IDFA	O
restrictions	O
called	O
CAID	O
.	O
</s>
