A
verifiable
claim
is
a
qualification,
achievement,
quality,
or
piece
of
information
about
an
entity's
background
such
as
a
name,
government
ID,
payment
provider,
home
address,
or
university
degree.
Such
a
claim
describes
a
quality
or
qualities,
property
or
properties
of
an
entity
which
establish
its
existence
and
uniqueness.
The
use
cases
outlined
here
are
provided
in
order
to
make
progress
toward
possible
future
standardization
and
interoperability
of
both
low
and
high-stakes
claims
with
the
goals
of
storing,
transmitting,
and
receiving
digitally
verifiable
proof
of
attributes
such
as
qualifications
and
achievements.
The
use
cases
in
this
document
focus
on
concrete
scenarios
that
the
technology
defined
by
the
group
should
address.
Status
of
This
Document
This
is
a
preview
Do
not
attempt
to
implement
this
version
of
the
specification.
Do
not
reference
this
version
as
authoritative
in
any
way.
Instead,
see
https://w3c.github.io/vc-use-cases/
for
the
Editor's
draft.
This
section
describes
the
status
of
this
document
at
the
time
of
its
publication.
Other
documents
may
supersede
this
document.
A
list
of
current
W3C
publications
and
the
latest
revision
of
this
technical
report
can
be
found
in
the
W3C
technical
reports
index
at
https://www.w3.org/TR/.
This
document
represents
a
concise
but
limited
collection
of
use
cases
readers
should
review
in
conjunction
with
the
proposed
Charter
for
a
Verifiable
Claims
Working
Group.
GitHub
Issues
are
preferred
for
discussion
of
this
specification.
Publication
as
a
Working
Group
Note
does
not
imply
endorsement
by
the
W3C
Membership.
This
is
a
draft
document
and
may
be
updated,
replaced
or
obsoleted
by
other
documents
at
any
time.
It
is
inappropriate
to
cite
this
document
as
other
than
work
in
progress.
This
document
was
produced
by
a
group
operating
under
the
W3C
Patent
Policy
.
The
Verifiable
Claims
Working
Group
at
the
W3C
is
developing
standards
for
expressing
and
exchanging
"
claims
"
that
have
been
verified
by
a
third
party
and
to
make
them
easier
and
more
secure
on
the
Web.
Note
This
document
does
NOT
attempt
to
define
an
architecture
for
the
support
of
Verifiable
Claims.
Instead
it
expresses
the
sorts
of
needs
that
real
users
have
that
could
be
addressed
through
support
for
some
sort
of
self-sovereign
claim
environment.
It
attempts
to
use
terminology
that
is
consistent
with
the
other
deliverables
of
the
Verifiable
Claims
Working
Group
(you
can
see
the
relevant
terms
in
Appendix
A).
1.1
Importance
of
this
work
Entities
(people,
organizations,
devices)
need
to
make
many
kinds
of
claims
as
part
of
their
everyday
activities.
As
more
and
more
of
these
important
activities
move
to
the
Internet,
entities
need
to
be
able
to
transmit
instantly
verifiable
claims
(e.g.,
about
their
location,
accomplishments,
value,
what-have-you).
From
educational
records
to
payment
account
access,
the
next
generation
of
web
applications
will
authorize
entities
to
perform
actions
based
on
rich
sets
of
credentials
issued
by
trusted
parties.
Human-
and
machine-mediated
decisions
about
job
applications,
account
access,
collaboration,
and
professional
development
will
depend
on
filtering
and
analyzing
growing
amounts
of
data.
It
is
essential
that
data
be
verifiable.
Standardization
of
digital
claim
technologies
makes
it
possible
for
many
stakeholders
to
issue,
earn,
and
trust
these
essential
records
about
their
counterparties,
without
being
locked
into
proprietary
platforms.
1.2
Use
case
model
This
document
presents
an
aggregate
use
case
model,
comprised
of
Needs,
Roles,
Tasks,
and
Sequences.
Taken
together,
these
models
define
the
use
cases
that
the
Verifiable
Claims
Working
Group
will
address.
User
needs
define
the
problem
space
verifiable
claims
addresses.
User
Roles
specify
the
roles
different
entities
play
when
interacting
with
verifiable
claims.
Tasks
define
the
functions
users
can
accomplish
and
sequences
demonstrate
how
tasks
might
be
realized
by
interactions
between
entities
over
time.
As
with
all
models,
this
use
case
model
is
neither
exhaustive
nor
complete.
The
listed
uses
cannot
capture
all
possible
use
cases.
Similarly,
the
models
do
not
completely
characterize
the
use
cases
represented.
However,
the
combined
model
is
intended
to
provide
specific,
coherent
guidance
for
the
work
ahead.
2.
User
Roles
There
are
four
roles
supported
by
verifiable
claims:
Issuer,
Verifier,
Subject,
and
Holder.
Figure
1
Verifiable
Claims
Roles
Issuer
The
entity
that
creates
a
claim
and
associates
it
with
a
particular
subject.
Verifier
The
entity
verifying
a
claim
about
a
given
subject.
Subject
The
entity
about
whom
a
claim
is
issued.
Holder
A
role
an
entity
may
perform
by
possessing
one
or
more
verifiable
credentials.
A
holder
is
usually,
but
not
always,
the
subject
of
the
verifiable
credentials
that
they
are
holding.
Holders
store
their
credentials
in
credential
repositories.
3.
User
Needs
Verifiable
claims
address
user
needs
in
a
number
of
key
domains:
Figure
2
Verifiable
Claims,
Example
Domains
for
User
Needs
3.1
Finance
The
Finance
domain
includes
banking,
brokerage,
insurance,
and
other
industries
where
there
is
a
high
value
placed
on
knowing
exactly
with
whom
you
are
dealing.
F.1
Reuse
know
your
customer
Jane
is
opening
an
account
at
MidBank
in
Finland.
As
part
of
that
process,
the
bank
asks
her
to
provide
two
from
a
variety
of
possible
sources
to
confirm
her
identity
—
a
so-called
"Know
Your
Customer"
check.
She
selects
government-supplied
verifiable
claims
that
confirm
she
receives
postal
mail
at
a
certain
address
and
that
she
has
a
national
ID
card.
Confirming
these
allows
the
bank
to
open
her
account
and
be
confident
in
her
identity
when
she
conducts
transactions.
Now
that
the
account
is
open,
Jane
is
issued
a
digitally-
signed
credential
for
her
checking
account
at
MidBank.
This
credential
verifies
that
Jane
has
an
account
at
MidBank
and
has
access
to
her
associated
checking
account.
Since
MidBank
(and
all
banks
in
Finland)
are
required
to
perform
"Know
Your
Customer"
checks
on
accounts,
this
credential
can
also
be
used
as
sufficient
verification
by
other
financial
institutions.
This
can
help
Jane
assure
destination
banks
that
she
is
verified,
thereby
allaying
concerns
about
misdirected
transactions
and
money
laundering.
F.2
Money
transfer
Susan
wants
to
send
funds
to
her
family
in
another
country
via
a
popular
money
transfer
service.
She
has
verifiable
claims
in
her
credential
repository
that
can
be
used
to
share
her
identity
profile
.
She
has
also
been
sent
a
claim
from
her
family
verifying
their
banking
information.
By
sharing
these
with
the
money
transfer
service,
they
can
automatically
verify
the
source
and
destination
of
funds,
thus
being
confident
in
the
delivery
of
those
funds
and
satisfying
various
regulations
regarding
prevention
of
money
laundering.
F.3
Closing
account
John
opens
a
checking
account
at
Big
Bank
Co
and
is
issued
a
verifiable
claim
indicating
that
the
account
exists,
that
the
bank
verified
John's
identity,
and
that
John
has
access
to
the
account.
Some
time
later,
John
is
moving
to
a
new
city
and
decides
to
close
that
account.
Big
Bank
Co
needs
to
revoke
that
claim
as
part
of
their
normal
account
closing
process.
F.4
Trying
out
a
new
service
Nikita
has
several
accounts
with
BigBank,
as
well
as
a
brokerage
account
with
WallStreetCo.
She
had
placed
all
of
her
claims
in
a
credential
repository
at
BigBank
that
came
free
when
she
opened
her
accounts.
WallStreetCo
is
now
offering
a
new
repository
that
has
an
interface
she
thinks
she
will
prefer.
Nikita
copies
her
claims
from
BigBank
into
the
repository
at
WallStreetCo
to
experiment
with
their
service,
but
continues
to
use
the
service
from
BigBank
while
she
is
testing.
F.5
New
bank
account
from
home
Alice
wants
to
open
a
new
bank
account.
BigOnlineBank
offers
the
ability
to
do
this
from
home
if
she
can
provide
electronic
credentials.
She
offers
government-issued
certificates
that
verify
her
identity
(address,
national
identity
number,
etc.),
and
opens
her
new
account
from
her
couch.
3.2
Education
The
education
domain
includes
all
levels
of
the
educational
experience;
from
primary
through
professional
continuing
education.
E.1
Digital
transcript
Joleen
is
the
registrar
of
Mega
University
and,
by
virtue
of
her
office,
is
responsible
for
the
integrity,
accuracy,
and
security
of
academic
records.
Joleen
has
been
a
pioneering
registrar
in
advocating
an
'extended
transcript'
that
includes
not
only
the
standard
set
of
course
grades
but
also
adds
supplementary
information
on
learner
competencies.
These
might
include
work
experiences
and
non-educational
but
marketable
skills.
Upon
the
request
of
her
students
Joleen
issues
a
digital
credential
that
includes
an
extended
transcript.
E.2
Taking
a
test
Eunice
is
about
to
take
her
ACT
(a
test
used
to
evaluate
her
readiness
for
college).
When
she
arrives
at
the
testing
center,
she
is
required
to
present
identification.
Her
government-issued
identity
certificate
is
acceptable,
as
the
verifiable
claims
contained
in
it
reflect
all
of
the
required
attributes
and
it
is
difficult
to
counterfeit.
E.3
Transferring
schools
Rocky
is
an
undergraduate
student
at
Wossamotta
U.
His
school
provides
a
credential
repository
service
to
all
students
and
alumni,
so
he
chooses
to
use
it.
In
his
third
year,
Rocky
decides
to
transfer
to
Moosylvania
Tech.
They
do
not
offer
a
service,
but
he
does
not
want
to
continue
to
use
the
service
of
his
old
(and
now
rival
school)
so
he
moves
his
claims
to
the
service
offered
by
his
bank
without
needing
to
have
them
reissued.
E.4
Online
classes
In
MOOC
and
other
online
learning
systems,
being
able
to
reliably
identify
participants
is
vital
to
ensure
the
individual
evaluation
and
certification.
Nick
is
participating
in
a
course
online
and
takes
a
test.
He
is
required
to
provide
his
credentials
to
prove
his
identity
before
the
test,
and
then
to
allow
the
system
to
issue
a
verifiable
claim
regarding
the
results
of
his
test.
3.3
Healthcare
Privacy
is
critically
important
in
the
healthcare
industry.
This
domain
looks
at
everything
from
physicial
interaction
to
connecting
patients
and
providers
with
service
organizations.
H.1
Prescribing
Barney
is
a
physician,
and
has
recently
become
board
certified
in
his
state.
The
state's
board
issues
Barney
a
digital
certificate
confirming
that
he
is
certified
to
practice
medicine
in
that
state.
Barney
can
now
use
this
certificate
when
writing
prescriptions
and
referrals,
thereby
improving
accountability
and
verifiability.
H.2
Online
pharmacy
iPharmacy
receives
a
prescription
for
Bob
electronically
from
a
local
clinic.
It
includes
a
certificate
about
the
physician
that
issued
the
prescription
as
well
as
one
about
Bob.
iPharmacy's
system
automatically
verifies
the
ability
of
the
physician
to
write
prescriptions,
as
well
as
Bob's
insurance
coverage.
When
Bob
arrives
to
pick
up
his
medication,
iPharmacy
further
correlates
his
identity
with
the
certificate,
thereby
improving
the
end-to-end
accountability
of
their
system.
H.3
Insurance
claim
Tracy
has
a
sore
throat
soon
after
moving
to
a
new
town.
She
finds
a
physician
through
her
health
care
network
and
goes
in
for
treatment.
She
is
a
new
patient,
so
the
clinic
needs
to
know
who
she
is
and
how
she
will
be
paying.
When
checking
in,
she
presents
her
verifiable
claim
that
demonstrates
her
identity
and
her
proof
of
insurance.
When
the
clinc
submits
this
to
the
insurance
company,
they
can
automatically
ascertain
that
she
submitted
her
proof
of
identity
and
insurance
to
the
provider
and
granted
the
physician
the
ability
to
submit
the
claim
for
payment.
H.4
Traveling
illness
John
is
on
the
vacation
of
a
lifetime,
travelling
the
world.
Falling
ill,
he
visits
a
health
clinic
in
a
country
in
which
he
does
not
live.
At
the
clinic
he
is
asked
for
proof
of
identity.
He
provides
a
credential
that
verifies
his
name
and
address,
but
elects
not
to
disclose
his
marital
status
nor
his
social
security
number,
as
those
are
neither
requested
nor
required
at
this
clinic.
He
further
marks
the
disclosure
as
expiring
in
30
days—he
does
not
want
his
information
verifiable
after
that
time.
3.4
Retail
The
retail
domain
encompasses
all
things
where
there
is
an
exchange
of
value
on
an
individual
level.
This
includes
brick-and-mortar
store
fronts,
web-only
venues,
and
even
person-to-person
sales.
R.1
Address
verification
Francis
has
found
the
perfect
pair
of
shoes.
When
processing
orders,
Giant
Shoe
Company
wants
to
be
certain
that
his
shipping
address
is
accurate
(inaccurate
addresses
are
very
expensive
in
terms
of
customer
service).
They
offer
a
discount
for
customers
who
make
verifiable
addresses
available
as
part
of
the
checkout
process.
Francis
offers
his
certificate
and
gets
the
perfect
shoes
for
even
less
than
he
expected.
R.2
Adult
beverages
June
goes
to
her
local
beer
and
wine
store
to
buy
a
bottle
of
wine.
She
submits
her
identity
credential
that
lets
the
liquor
store
owner
know
that
she
is
over
21
without
having
to
reveal
her
actual
date
of
birth,
her
address,
or
her
state
ID
number.
R.3
Fraud
detection
On
a
bright
Sunday,
Oskar
remembers
that
he
still
needs
to
buy
his
wife
a
precious
gift
for
their
wedding
anniversary.
However,
he
is
acutely
aware
that
it
is
precisely
in
weekends
that
gangs
set
up
fraudulent
web
shops
that
claim
to
sell
such
gifts,
while
in
fact
they
only
take
the
cash,
and
disappear
on
Mondays.
So
before
actually
purchasing
a
gift
from
the
web
shop
of
his
choice,
he
requests
the
shop
to
provide
a
credential
issued
by
the
chamber
of
commerce,
that
contains
proof
of
legitimacy.
After
having
verified
that
the
shop
is
legit,
he
can
purchase
his
gift.
3.5
Professional
Credentials
In
many
aspects
of
life
it
is
important
to
know
that
entities
are
who
they
say
they
are,
and
that
they
can
do
what
they
say.
Professional
accreditation
is
one
way
of
learning
about
the
abilities
of
an
entity.
Being
able
to
verify
these
credentials
is
essential
to
their
value.
C.1
Find
a
doctor
Jason
is
looking
for
a
new
primary
care
physician.
His
health
provider
includes
information
on
their
web
site
about
the
physicians
they
have
on
staff,
including
verifiable
credentials
about
their
education,
board
certification,
and
continuing
education.
Jason
can
verify
these
credentials
and
be
confident
that
his
new
physician
satisfies
his
requirements.
C.2
Busy
doctor
Barney
was
a
board-certified
physician,
but
he
ran
out
of
time
to
complete
his
contuning
education
requirements
and
his
certification
lapsed.
Since
the
board
can
revoke
his
certification,
credential
verifiers
will
automatically
be
aware
that
he
can
no
longer
issue
prescriptions
or
perform
medical
procedures.
C.3
Bad
university
Jane
was
issued
a
certificate
by
BigTraining
Co.,
indicating
that
she
was
a
trained
Project
Manager.
It
was
later
discovered
that
BigTraining
Co.
was
not
actually
training
anyone,
and
their
organization's
certificate
was
revoked
via
the
US
Department
of
Education's
Accreditation
Database.
Jane's
credential
is
therefore
invalid,
and
prospective
employers
will
be
aware
of
this
when
they
check
her
certifications.
C.4
New
employer
Jessica
is
a
medical
doctor
practicing
in
the
United
States.
She
has
a
variety
of
digital
claims
that
explain
her
qualifications,
schooling,
continuing
education
achievements,
and
board
certifications.
These
are
all
stored
in
the
credential
repository
provided
by
her
employer.
When
she
is
offered
a
position
with
another
health
provider
network,
she
can
automatically
transfer
all
of
these
claims
to
her
new
employer.
C.5
Social
authority
Josie
is
a
healthcare
worker
that
has
created
a
profile
on
a
professional
social
network
to
make
herself
readily
available
for
new
opportunities
in
the
workforce.
She
lists
her
employment
history
and
credentials
including
degrees,
certificates,
and
digital
badges.
The
website
requests
verification
of
her
credential
claims
in
order
for
her
credentials
to
be
visible
when
she
posts
messages.
Josie
authorizes
the
sharing
of
the
relevant
claims
with
the
website,
and
the
site
verifies
them
before
allowing
Josie
to
expose
them.
"Freedom?"
is
an
online
forum
that
encourages
free
discussion
about
issues
controversial
in
Freedonia.
The
forum
allows
users
to
register
anonymous
accounts,
but
it
also
allows
users
to
obtain
badges
based
upon
real-world
certifications.
Paula
has
been
certified
as
an
aid
worker,
and
wishes
that
information
to
be
marked
on
her
posts.
She
shares
her
certificate
with
the
forum,
but
limits
it
to
only
verifying
that
she
is
the
holder
of
the
certificate,
that
she
is
the
subject
of
it,
and
that
she
is
an
aid
worker.
In
this
way
she
maintains
her
anonymity
in
this
controversial
forum
while
still
being
able
to
assist
her
fellow
countrymen.
C.6
Job
applicant
Software
Co.
has
posted
an
open
position
online
and
they
are
receiving
thousands
of
applications.
Cindy
has
applied
for
the
job.
Unlike
many
applicants,
she
has
attached
her
education
credentials—college
degree,
additional
specific
software
training,
etc.
Software
Co.
evaluates
these
credentials
automatically
as
they
receive
her
application.
Because
her
materials
are
verifiable
and
verified,
her
application
is
immediately
forwarded
as
a
viable
candidate.
3.6
Legal
Identity
For
many
transactions,
an
entity
must
be
able
to
prove
some
aspect
of
their
identity
in
a
way
that
can
be
quickly
verified.
Governments
and
other
widely
recognized
entities
are
well
positioned
to
provide
such
identification
in
a
verifiable
digital
form.
L.1
Digital
driving
license
Asako
just
passed
the
final
test
to
receive
a
drivers
license.
As
she
is
still
a
new
driver,
and
may
be
pulled
over
for
a
traffic
violation,
she
would
like
to
receive
a
credential
that
asserts
a
claim
that
she
has
right
to
drive
a
car.
She
requests
a
credential
from
the
certifying
authority
(
issuer
)
that
she
can
use
to
prove
to
the
officer
(
credential
verifier
)
that
her
claim
is
valid.
L.2
Seamless
immigration
Tom
is
a
frequent
international
traveler.
In
order
to
speed
processing
through
immigration
check
points,
he
applies
for
a
digital
passport
from
his
governmental
authority.
After
satisfying
background
check
requirements,
the
authority
issues
Tom
an
electronic
version
of
his
passport.
This
version
is
verifiable
and
retains
a
history
of
all
the
places
he
visits
so
that
immigration
officials
can
quickly
and
easily
evaluate
his
suitability
as
a
visitor
to
their
country.
Once
they
are
satisfied,
they
will
automatically
add
the
details
of
this
new
visit
to
Tom's
passport.
L.3
Speedy
air
travel
Security
for
air
travel
is
more
and
more
rigorous,
requiring
more
and
more
time
to
validate
each
passenger.
Ivan
has
a
collection
of
verifiable
claims
that
are
assembled
into
his
air
travel
Identity
Profile
.
When
Ivan
needs
to
pass
through
a
security
checkpoint
at
his
airport,
he
presents
this
profile
before
entering
the
line.
Because
his
identification
can
be
immediately
and
automatically
verified,
he
is
permitted
to
skip
the
long
line
and
go
straight
to
the
metal
detector.
L.4
Refugee
crisis
Thousands
of
people
each
year
are
displaced
because
of
man-made
and
natural
disasters.
Anoushka
is
one
such,
having
been
forced
to
flee
her
village
along
with
her
mother
and
younger
brother.
They
reach
an
IFRC
center
just
across
the
border
in
a
relatively
safe
area,
but
with
no
documentation.
Since
the
government
of
her
homeland
is
in
turmoil,
there
is
no
way
for
the
IFRC
staff
to
easilty
establish
their
identities.
Fortunately,
Anoushka
had
been
issued
a
self-soverign
proof
of
birth,
attached
to
which
is
the
proof
of
birth
and
marriage
for
her
parents.
She
is
able
to
retrieve
this
because
it
is
available
from
many
places
often
the
Internet.
Since
it
is
verifiable,
the
IFRC
is
comfortable
vouching
for
them
and
resettling
them
in
a
safer
area
for
the
duration
of
the
conflict.
4.
User
Tasks
Use
cases
are
often
used
as
a
driver
for
requirements.
While
the
users
of
verifiable
claims
have
needs
across
many
domains,
the
tasks
associated
with
those
needs
span
the
domains.
This
section
summarizes
those
tasks,
as
well
as
requirements
related
to
the
tasks,
and
maps
the
tasks
and
requirements
back
to
the
associated
needs.
Note
It
is
worth
noting
that
the
subject
may
or
may
not
be
the
same
entity
as
the
holder.
There
are
no
tasks
in
these
examples
that
require
participation
of
the
subject.
Figure
3
Verifiable
Claims
User
Tasks
4.1
Issue
Claim
Requirement
It
MUST
be
possible
for
any
entity
to
issue
a
verifiable
claim
.
Motivation
Individuals
and
organizations
need
a
way
to
issue
claims
about
themselves
or
others
that
can
be
verified
and
trusted.
It
MUST
be
possible
for
the
holder
of
a
claim
to
restrict
the
amount
of
information
exposed
in
a
claim
they
choose
to
share.
It
also
MUST
be
possible
for
the
holder
to
limit
the
duration
for
which
that
information
is
shared.
Motivations
Credentials
may
be
issued
about
a
subject
that
include
multiple
attributes,
only
some
of
which
are
required
when
verifying
a
specific
criteria
is
satisfied.
The
holder
should
have
the
ability
to
satisfy
the
criteria
without
revealing
additional
attributes
that
are
not
required.
It
MUST
be
possible
for
a
verifier
to
verify
that
the
credential
is
an
authentic
statement
of
an
issuer's
claims
about
the
subject
.
The
verifying
entity
must
have
the
capability
to
connect
the
issuer’s
identity
to
its
credential
identifier
and
the
subject's
identity
to
their
identifier
as
indicated
in
the
credential.
The
issuer’s
verification
information,
such
as
its
public
key,
must
be
discoverable
from
the
credential
record
and
verifiably
linked
to
the
issuer.
It
MUST
be
possible
to
do
this
in
an
automated
fashion.
Motivations
In
many
environments
(such
as
order
processing)
information
such
as
a
payer's
address,
citizenship,
or
age
need
to
be
automatically
verified
in
order
to
complete
the
transaction.
It
MUST
be
possible
for
a
verifier
to
determine
what
pairs
of
(credential
type,
issuer)
it
accepts
as
valid,
i.e.
trusts
to
be
valid,
for
what
purposes.
It
SHOULD
be
possible
that
VCs
that
may
contain
the
same
information,
but
that
are
issued
by
different
issuers,
are
all
acceptable
for
one
purpose,
but
only
specific
issuers
would
be
allowed
for
another
purpose.
Every
verifier
MUST
make
its
own
decisions
in
this
regard.
As
a
consequence,
it
MUST
be
possible
for
a
verifier
to
obtain
all
information
that
it
finds
relevant
for
making
such
determinations,
and
hence
also
for
issuer
s
to
publish
(advertise)
such
information.
It
is
envisaged
that
such
information
would
include
syntax
and
semantics
of
the
claims
in
the
credential,
an
endpoint
at
which
the
issuer
issues
these
credentials,
and
(optionally)
other
meta-data,
such
as
liability
that
the
issuer
takes,
compensations
for
issue/use
of
such
credentials,
procedures
that
the
issuer
has
followed
to
verify
the
truthfulness
of
issued
claims,
etc.
Motivations
Whenever
a
holder
requests
a
verfier
to
provide
a
product
or
service,
the
verfier
must
return
a
query
for
the
claims
(from
issuer
s
that
it
trusts,
and)
that
it
needs
to
decide
whether
or
not
to
provide
the
requested
product
or
service.
In
order
for
the
verfier
to
decide
whether
or
not
it
trusts
credentials
from
identifiable
issuer
s,
it
needs
information,
e.g.
about
the
kinds
of
claims
in
such
credentials,
the
way
that
the
issuer
has
verified
them,
and
more.
This
requirement
becomes
increasingly
important
as
the
transactions
that
the
verfier
must
decide
on,
come
with
a
higher
value
(and
hence
a
higher
risk).
Needs
every
use-case
4.5
Store
/
Move
Claim
Requirement
It
MUST
be
possible
for
the
holder
of
a
claim
to
store
that
claim
in
one
or
more
credential
repositories
.
It
MUST
also
be
possible
for
the
holder
to
move
a
claim
among
credential
repositories,
and
to
do
so
without
requesting
a
new
claim
from
the
claim
issuer.
Motivation
A
claim
is
under
the
control
of
its
holder
.
That
holder
will
choose
where
their
claims
are
stored
based
upon
a
variety
of
factors
(e.g.,
employer
requirements,
convenience,
service
levels,
provider
cost,
business
intelligence).
The
holder
needs
to
be
able
to
easily
choose
among
various
credential
repositories,
and
also
to
be
able
to
migrate
their
claims
to
another
without
requesting
new
claims
from
the
claim
issuer
.
It
MUST
be
possible
for
the
issuer
of
a
claim
to
revoke
it,
after
which
it
will
no
longer
satisfy
verification
procedures.
Motivation
An
entity
(
issuer
)
discovers
that
a
claim
they
have
issued
and
are
endorsing
for
an
end
user
(
subject
),
is
no
longer
valid
and
wishes
to
revoke
the
issued
claim.
Focal
Use
Cases
are
meant
to
provide
examples
where
a
blend
of
features
from
verifiable
claims
standard
may
be
used
together
to
solve
complex
or
challenging
marketplace
needs.
5.1
Citizenship
by
Parentage
Background
Sam
wants
to
claim
US
citizenship
because
his
mother
is
American.
Sam
has
a
digital
birth
certificate
from
Kenya,
where
he
was
born
while
his
Mother
was
in
the
Peace
corps.
He
also
has
a
digital
version
of
his
mother's
US
passport.
Because
his
mother’s
name
changed
between
his
birth
and
the
issuance
of
the
passport,
Sam
also
has
a
marriage
license
with
her
maiden
and
married
names.
Sam
is
applying
for
a
new
passport
from
the
US
Secretary
of
State.
Distinction
This
use
case
is
challenging
because
the
mother’s
name
changed,
by
marriage,
between
the
issuance
of
the
birth
certificate
and
passport.
Scenario
Sam’s
mother
emailed
him
the
certificate,
license,
and
passport
as
independent
Verifiable
Credentials.
He
then
creates
a
verifiable
presentation
which
includes
those
credentials,
a
statement
of
their
relationship
to
each
other
and
his
relationship
to
his
mother.
He
then
visits
the
US
Secretary
of
State
website,
creates
an
account,
starts
the
application
for
a
passport,
and
uploads
his
new
verifiable
presentation
as
supporting
evidence.
After
processing
the
application,
Sam
is
issued
both
a
traditional
passport
and
a
new
digital
passport.
Verifiable
Credentials
Birth
Certificate
Establishes
relationship
to
mother
with
maiden
name
Marriage
License
Establishes
mother's
name
change
Mother’s
Passport
Establishes
mother's
US
citizenship
Sam’s
Passport
Establishes
Sam
is
the
child
in
the
birth
certificate
Verifiable
Presentation
A
verifiable
presentation
which
includes
those
three
credentials,
adds
his
name,
photo,
and
demographic
data
along
with
the
assertion
that
He
is
the
child
in
the
birth
certificate.
The
mother
in
the
birth
certificate,
the
person
in
the
passport,
the
spouse
in
the
marriage
license
are
all
the
same
person.
Trust
Hierarchy
Sam
is
legally
liable
for
his
claim
to
the
rights
of
citizenship.
The
state
department
is
on
the
hook
for
verifying
the
underlying
credentials
and
Sam’s
claims,
including
correlating
against
any
additional
data
they
might
already
have.
Threat
model
Threat:
Terrorist
/
Identity
fraud.
A
bad
actor
could
be
impersonating
Sam
to
attain
a
passport.
Of
course,
if
a
bad
actor
were
to
be
able
to
collect
the
required
verifiable
credentials—mother’s
passport,
birth
certificate,
and
marriage
license,
that
actor
has
already
significantly
compromised
the
system.
Response:
Identity
assurance
based
on
the
presentation
and
other
data,
above
and
beyond
what
is
in
the
presentation
and
the
claims.
Response:
Identity
assurance
based
on
the
contents
of
the
claims,
potentially
with
enhanced
data
embedded
in
the
claims,
i.e.,
data
not
currently
in
passports,
birth
certificates,
or
marriage
license.
For
example,
a
biometric
template
could
be
embedded
in
the
birth
certificate
claim
and
that
template
could
be
used
for
interactive
identity
assurance
at
the
time
of
submitting
the
presentation.
Threat:
Exposure
of
private
information.
By
storing
potentially
compromising
information
in
credentials
and
sending
them
over
the
network,
we
are
increasing
the
attack
surface
for
the
subjects
of
those
credentials.
Response:
Encrypt
the
claims
(once
by
issuer,
every
verifier
gets
the
same
encrypted
blob)
Response:
Encrypt
the
claims
uniquely
for
each
verifier.
This
may
leak
usage
data
to
the
issuer,
assuming
the
holder
must
ask
for
a
new,
encrypted
credential
for
each
verifier.
Response:
Blind
the
claims
uniquely
for
each
verifier.
Response:
Encrypt
the
presentation
uniquely
for
each
verifier.
No
issuer
involved.
5.2
International
Travel
with
Minor
and
Upgrade
Background
Malathi
is
traveling
internationally
with
her
8-month-old
son,
Anand.
His
father,
Rajesh,
is
staying
home.
Malathi
has
enough
frequent
flyer
miles
to
upgrade
the
ticket
to
first
class.
Distinction
This
use
case
is
difficult
because:
Current
US
passports
do
not
establish
explicit
relationship
between
parent
and
child.
When
one
parent
travels
with
a
minor,
the
other
parent
is
required
to
grant
permission
for
the
trip,
thus
implying
guardianship
or
responsibility.
The
DID
or
other
Digital
Identity
system
replaces
the
role
of
the
notary
in
the
paper/physical
world
Credentials
must
be
coordinated
between
two
verifiers
(agent
and
airline)
for
two
individuals,
and
a
digital
coupon
is
used.
The
relationship
of
the
minor
to
the
non-traveling
parent
must
be
established,
in
order
for
the
permission
to
be
considered.
In
the
minor's
passport
case,
the
subject
is
not
the
holder
of
the
verifiable
credential.
The
holder(s)
of
the
passport
are
parents,
not
the
minor.
Scenario
Malathi
obtains
permission
from
Rajesh
stating
she
is
allowed
to
take
the
baby
out
of
the
country.
Prior
to
booking
the
trips,
Malathi
visits
HappyAir.com
to
request
an
upgrade
to
first
class.
HappyAir
issues
a
verifiable
credential
redeemable
for
a
first
class
upgrade
on
an
international
flight.
She
books
the
plane
tickets
through
her
travel
agent
who
adds
the
lap
child
to
the
ticket.
HappyAir
verifies
that
Malathi
has
a
signed
statement
from
Anand’s
other
parent
stating
that
she
may
exit
the
country
with
him.
Verifiable
Credentials
Malathi's
passport
Establishes
identity
of
the
traveling
parent
Anand's
passport
Establishes
identity
of
the
minor
Anand's
Birth
Certificate
Establishes
relationship
to
parents
and
provides
link
from
Rajesh
to
Anand
that
qualifies
the
permission
to
travel
Permission
to
travel
from
Rajesh
Grants
permission
from
non-traveling
parent
for
minor
to
travel.
Identity
matches
identity
of
the
parent
in
the
birth
certificate,
establishing
relevance.
Issue
1
This
is
content
from
the
prior
discussion—remove
the
following
points?
Parents
are
the
holders
of
the
passport
credential
Parents
must
present
the
passport
credential
In
order
for
one
parent
to
present
the
passport
credential
alone,
they
must
give
mutual
permission.
This
replaces
the
role
of
a
notarized
permission
document
Upgrade
coupon
for
first
class
ticket
Introduces
commercial
value
in
a
verifiable
credential
Submitted
to
HappyAir,
includes
Malathi
and
Anand's
passport,
assertion
of
permission,
birth
certificate
and
Frequent
Flyer
coupon.
Trust
Hierarchy
Malathi
is
liable
for
her
claim
of
parentage
as
well
as
securing
right
to
admission
for
herself
and
her
son
at
their
destination
(visa
may
be
required).
Malathi
and
Rajesh
are
both
liable
for
attestation
of
permission
to
fly
with
Anand
without
the
other
parent.
Malathi
is
liable
for
the
cost
of
her
ticket
and
her
son’s
ticket.
The
agency
is
liable
for
issuing
valid
tickets
and
for
verifying
the
credentials
provided
by
the
travelers.
The
airline
is
liable
for
issuing
tickets
and,
ultimately,
fulfilling
the
terms
of
travel
[does
the
airline
issue
tickets
or
do
the
agents?].
The
airline
is
liable
for
accepting
the
upgrade
coupons
at
ticketing.
The
airline
is
liable
for
verifying
the
credentials
in
the
birth
certificate
match
the
credentials
in
the
permission
letter.
The
check-in
agent,
TSA
agent,
and
passport
control
at
the
destination
are
liable
for
identity
assurance
at
various
points
of
travel,
using
information
contained
in
the
verifiable
credentials.
Threat
model
Threat:
Stolen
Key.
Malathi
steals
Rajesh’s
key
in
order
to
fake
travel
permission.
(Kidnapping
her
own
kids
and
fleeing
Rajesh.)
Response:
Rajesh
could
store
his
key
with
a
trusted
third
party,
such
as
an
attorney.
Response:
Rajesh
could
use
a
hardware
wallet
with
pin
or
biometric.
Response:
Rajesh
could
use
a
passphrase
on
his
key
Threat:
Stolen
Key
2
Ticket
purchaser
has
Malathi’s
credentials,
impersonating
her
to
purchase
a
ticket.
This
could
enable
a
third-party
kidnapping.
Response:
Travel
permission
can
be
restricted
to
specific
date
and
or
trip
minimizing
abuse
potential.
Response:
Embed
identifying
characteristics
or
biometric
into
the
credentials
so
that
verifiers
can
independently
verify
the
subject
in
front
of
them
is
the
subject
in
the
credential.
Response:
Malathi
could
use
a
hardware
wallet
with
pin
or
biometric.
Response:
Malathi
could
use
a
passphrase
on
her
key
Threat:
Impersonating
traveler.
Handled
by
identity
assurance,
using
information
within
the
credentials
Response:
Identity
assurance
based
on
the
presentation
and
other
data,
above
and
beyond
what
is
in
the
presentation
and
the
claims.
Response:
Identity
assurance
based
on
the
contents
of
the
claims,
potentially
with
enhanced
data
embedded
in
the
claims,
i.e.,
data
not
currently
in
passports,
birth
certificates,
or
marriage
license.
For
example,
a
biometric
template
could
be
embedded
in
the
birth
certificate
claim
and
that
template
could
be
used
for
interactive
identity
assurance
at
the
time
of
submitting
the
presentation.
Threat:
False
Parent
Someone
other
than
than
Rajesh,
e.g.,
Fred,
signs
the
travel
permission
with
a
valid
key,
allowing
Malathi
to
travel
without
Rajesh’s
permission.
Response:
Fred’s
actions
are
fraudulent.
Captured
in
the
signed
statement,
it
would
provide
evidence
for
prosecution.
Response:
Fred’s
credentials
won’t
match
those
in
Anand’s
birth
certificate.
By
comparing
the
credentials,
HappyAir
can
prevent
this
attack
Threat:
Exposure
of
private
information.
By
storing
potentially
compromising
information
in
credentials
and
sending
them
over
the
network,
we
are
increasing
the
attack
surface
for
the
subjects
of
those
credentials.
Response:
Encrypt
the
claims
(once
by
issuer,
every
verifier
gets
the
same
encrypted
blob)
Response:
Encrypt
the
claims
uniquely
for
each
verifier.
This
may
leak
usage
data
to
the
issuer,
assuming
the
holder
must
ask
for
a
new,
encrypted
credential
for
each
Verifier.
Response:
Blind
the
claims
uniquely
for
each
verifier.
Response:
Encrypt
the
presentation
uniquely
for
each
verifier.
No
issuer
involved
Threat:
Stolen
coupon
Rajesh
falsifies
the
upgrade
coupon.
Response:
HappyAir
signs
the
coupon
with
secure
credentials.
Response:
Travel
agent
verifies
the
coupon
through
a
distributed
status
registry,
verifying
it
is
still
valid
6.
User
Sequences
The
transaction
examples
in
this
section
show
basic
ways
in
which
verifiable
claims
might
be
used.
They
are
not
meant
to
be
architecturally
constraining.
Instead,
they
are
meant
to
help
illustrate
the
basic
way
it
could
be
done
in
a
typical
commerce
situation.
Again—please
remember
that
it
is
just
an
example,
and
should
not
be
thought
of
as
the
canonical
way
such
a
claims
environment
must
be
implemented.
6.1
How
a
Verifiable
Claim
Might
Be
Created
In
this
first
example,
a
user
will
request
a
verifiable
claim—a
confirmation
of
their
identity.
Consider
this
illustration:
Figure
4
Verifiable
Claim
Creation
Flow
Diagram
Expanding
on
these
steps:
Jane
asks
her
User
Agent
to
help
her
get
a
verifiable
claim
about
her
identity.
Her
user
agent
connects
her
to
a
certificate
issuer
that
is
able
to
verify
her
identity.
The
issuer
examines
her
documentation.
They
are
satisfied,
so
the
issuer
generates
a
verifiable
claim
for
Jane
that
includes
information
about
her
identity
linked
to
their
own
trusted
credential
.
The
issuer
delivers
the
credential
back
to
Jane's
User
Agent.
Jane
views
the
credential
to
ensure
it
reflects
her
requirements.
When
she
is
satisfied,
she
instructs
her
User
Agent
to
save
the
verifiable
claim
so
she
can
use
it
in
the
future.
The
credential
repository
shows
Jane
three
verifiable
claims
it
knows
of
that
can
assert
this
claim
(e.g.,
her
passport,
driving
license,
and
birth
certificate).
Jane
selects
one
of
these
and
authorizes
that
it
be
shared
with
the
merchant.
The
credential
repository
returns
the
selected
claim
as
a
response
to
the
user
agent-supported
API
call,
which
in
turn
delivers
it
to
the
merchant.
The
merchant's
server
verifies
that
the
claim
is
valid
and
satisfies
the
requirement.
The
merchant
redirects
the
user
agent
to
the
web
site
with
appropriate
authorization.
A.
Terminology
This
section
is
non-normative.
The
following
terms
are
used
to
describe
concepts
in
this
specification.
A
set
of
one
or
more
claims
made
by
an
issuer
.
A
verifiable
credential
is
a
tamper-evident
credential
that
has
authorship
that
can
be
cryptographically
verified.
Verifiable
credentials
can
be
used
to
build
verifiable
presentations
,
which
can
also
be
cryptographically
verified.
The
claims
in
a
credential
can
be
about
different
subjects
.
entity
A
thing
with
distinct
and
independent
existence,
such
as
a
person,
organization,
or
device
that
performs
one
or
more
roles
in
the
ecosystem.
Data
derived
from
one
or
more
verifiable
credentials
,
issued
by
one
or
more
issuers
,
that
is
shared
with
a
specific
verifier
.
A
verifiable
presentation
is
a
tamper-evident
presentation
encoded
in
such
a
way
that
authorship
of
the
data
can
be
trusted
after
a
process
of
cryptographic
verification.
Certain
types
of
verifiable
presentations
might
contain
data
that
is
synthesized
from,
but
do
not
contain,
the
original
verifiable
credentials
(for
example,
zero-knowledge
proofs).
The
editors
are
thankful
to
the
contributions
from
the
Web
Payments
Workshop,
the
Web
Payments
Community
Group,
the
Web
Payments
Interest
Group,
the
Credentials
Community
Group,
the
Verifiable
Claims
Task
Force,
and
the
Verifiable
Claims
Working
Group.