CFR21 Part11
English
(Original
Text)
A
General
Provisions
§
11.1
Scope.
(a)
The
regulations
in
this
part
set
forth
the
criteria
under
which
the
agency
considers
electronic
records,
electronic
signatures,
and
handwritten
signatures
executed
to
electronic
records
to
be
trustworthy,
reliable,
and
generally
equivalent
to
paper
records
and
handwritten
signatures
executed
on
paper.
(b)
This
part
applies
to
records
in
electronic
form
that
are
created,
modified,
maintained,
archived,
retrieved,
or
transmitted,
under
any
records
requirements
set
forth
in
agency
regulations.
This
part
also
applies
to
electronic
records
submitted
to
the
agency
under
requirements
of
the
Federal
Food,
Drug,
and
Cosmetic
Act
and
the
Public
Health
Service
Act,
even
if
such
records
are
not
specifically
identified
in
agency
regulations.
However,
this
part
does
not
apply
to
paper
records
that
are,
or
have
been,
transmitted
by
electronic
means.
(c)
Where
electronic
signatures
and
their
associated
electronic
records
meet
the
requirements
of
this
part,
the
agency
will
consider
the
electronic
signatures
to
be
equivalent
to
full
handwritten
signatures,
initials,
and
other
general
signings
as
required
by
agency
regulations,
unless
specifically
excepted
by
regulation(s)
effective
on
or
after
august
20,
1997.
(d)
Electronic
records
that
meet
the
requirements
of
this
part
may
be
used
in
lieu
of
paper
records,
in
accordance
with
§
11.2,
unless
paper
records
are
specifically
required.
(e)
Computer
systems
(including
hardware
and
software),
controls,
and
attendant
documentation
maintained
under
this
part
shall
be
readily
available
for,
and
subject
to,
FDA
inspection.
§
11.2
Implementation
(a)
For
records
required
to
be
maintained
but
not
submitted
to
the
agency,
persons
may
use
electronic
records
in
lieu
of
paper
records
or
electronic
signatures
in
lieu
of
traditional
signatures,
in
whole
or
in
part,
provided
that
the
requirements
of
this
part
are
met.
(b)
For
records
submitted
to
the
agency,
persons
may
use
electronic
records
in
lieu
of
paper
records
or
electronic
signatures
in
lieu
of
traditional
signatures,
in
whole
or
in
part,
provided
that:
(1)
The
requirements
of
this
part
are
met;
and
(2)
The
document
or
parts
of
a
document
to
be
submitted
have
been
identified
in
public
docket
No.
92S–
0251
as
being
the
type
of
submission
the
agency
accepts
in
electronic
form.
This
docket
will
identify
specifically
what
types
of
documents
or
parts
of
documents
are
acceptable
for
submission
in
electronic
form
without
paper
records
and
the
agency
receiving
unit(s)
(e.g.,
specific
center,
office,
division,
branch)
to
which
such
submissions
may
be
made.
Documents
to
agency
receiving
unit(s)
not
specified
in
the
public
docket
will
not
be
considered
as
official
if
they
are
submitted
in
electronic
form;
paper
forms
of
such
documents
will
be
considered
as
official
and
must
accompany
any
electronic
records.
Persons
are
expected
to
consult
with
the
intended
agency
receiving
unit
for
details
on
how
(e.g.,
method
of
transmission,
media,
file
formats,
and
technical
protocols)
and
whether
to
proceed
with
the
electronic
submission.
§
11.3
Definitions.
(a)
The
definitions
and
interpretations
of
terms
contained
in
section
201
of
the
act
apply
to
those
terms
when
used
in
this
part.
(b)
The
following
definitions
of
terms
also
apply
to
this
part:
(1)
Act
means
the
Federal
Food,
Drug,
and
Cosmetic
Act
(secs.
201–903
(21
U.S.C.
321–393)).
(2)
Agency
means
the
Food
and
Drug
Administration.
(3)
Biometrics
means
a
method
of
verifying
an
individual’s
identity
based
on
measurement
of
the
individual’s
physical
feature(s)
or
repeatable
action(s)
where
those
features
and/or
actions
are
both
unique
to
that
individual
and
measurable.
(4)
Closed
system
means
an
environment
in
which
system
access
is
controlled
by
persons
who
are
responsible
for
the
content
of
electronic
records
that
are
on
the
system.
(5)
Digital
signature
means
an
electronic
signature
based
upon
cryptographic
methods
of
originator
authentication,
computed
by
using
a
set
of
rules
and
a
set
of
parameters
such
that
the
identity
of
the
signer
and
the
integrity
of
the
data
can
be
verified.
(6)
Electronic
record
means
any
combination
of
text,
graphics,
data,
audio,
pictorial,
or
other
information
representation
in
digital
form
that
is
created,
modified,
maintained,
archived,
retrieved,
or
distributed
by
a
computer
system.
(7)
Electronic
signature
means
a
computer
data
compilation
of
any
symbol
or
series
of
symbols
executed,
adopted,
or
authorized
by
an
individual
to
be
the
legally
binding
equivalent
of
the
individual’s
handwritten
signature.
(8)
Handwritten
signature
means
the
scripted
name
or
legal
mark
of
an
individual
handwritten
by
that
individual
and
executed
or
adopted
with
the
present
intention
to
authenticate
a
writing
in
a
permanent
form.
The
act
of
signing
with
a
writing
or
marking
instrument
such
as
a
pen
or
stylus
is
preserved.
The
scripted
name
or
legal
mark,
while
conventionally
applied
to
paper,
may
also
be
applied
to
other
devices
that
capture
the
name
or
mark.
(9)
Open
system
means
an
environment
in
which
system
access
is
not
controlled
by
persons
who
are
responsible
for
the
content
of
electronic
records
that
are
on
the
system.
Subpart
B
Electronic
Records
B
§11.10
Controls
for
closed
systems.
Persons
who
use
closed
systems
to
create,
modify,
maintain,
or
transmit
electronic
records
shall
employ
procedures
and
controls
designed
to
ensure
the
authenticity,
integrity,
and,
when
appropriate,
the
confidentiality
of
electronic
records,
and
to
ensure
that
the
signer
cannot
readily
repudiate
the
signed
record
as
not
genuine.
Such
procedures
and
controls
shall
include
the
following:
11.10
(a)
Validation
of
systems
to
ensure
accuracy,
reliability,
consistent
intended
performance,
and
the
ability
to
discern
invalid
or
altered
records.
11.10
(b)
The
ability
to
generate
accurate
and
complete
copies
of
records
in
both
human
readable
and
electronic
form
suitable
for
inspection,
review,
and
copying
by
the
agency.
Persons
should
contact
the
agency
if
there
are
any
questions
regarding
the
ability
of
the
agency
to
perform
such
review
and
copying
of
the
electronic
records.
11.10
(c)
Protection
of
records
to
enable
their
accurate
and
ready
retrieval
throughout
the
records
retention
period
11.10
(d)
Limiting
system
access
to
authorized
individuals.
11.10
(e)
Use
of
secure,
computer-generated,
time-stamped
audit
trails
to
independently
record
the
date
and
time
of
operator
entries
and
actions
that
create,
modify,
or
delete
electronic
records.
Record
changes
shall
not
obscure
previously
recorded
information.
Such
audit
trail
documentation
shall
be
retained
for
a
period
at
least
as
long
as
that
required
for
the
subject
electronic
records
and
shall
be
available
for
agency
review
and
copying.
11.10
(f)
Use
of
operational
system
checks
to
enforce
permitted
sequencing
of
steps
and
events,
as
appropriate.
11.10
(g)
Use
of
authority
checks
to
ensure
that
only
authorized
individuals
can
use
the
system,
electronically
sign
a
record,
access
the
operation
or
computer
system
input
or
output
device,
alter
a
record,
or
perform
the
operation
at
hand.
11.10
(h)
Use
of
device
(e.g.,
terminal)
checks
to
determine,
as
appropriate,
the
validity
of
the
source
of
data
input
or
operational
instruction.
11.10
(i)
Determination
that
persons
who
develop,
maintain,
or
use
electronic
record/electronic
signature
systems
have
the
education,
training,
and
experience
to
perform
their
assigned
tasks.
11.10
(j)
The
establishment
of,
and
adherence
to,
written
policies
that
hold
individuals
accountable
and
responsible
for
actions
initiated
under
their
electronic
signatures,
in
order
to
deter
record
and
signature
falsification.
11.10
(k)
Use
of
appropriate
controls
over
systems
documentation
including:
(1)
Adequate
controls
over
the
distribution
of,
access
to,
and
use
of
documentation
for
system
operation
and
maintenance.
(2)
Revision
and
change
control
procedures
to
maintain
an
audit
trail
that
documents
time-
sequenced
development
and
modification
of
systems
documentation.
B
§11.30
Controls
for
open
systems.
Persons
who
use
open
systems
to
create,
modify,
maintain,
or
transmit
electronic
records
shall
employ
procedures
and
controls
designed
to
ensure
the
authenticity,
integrity,
and,
as
appropriate,
the
confidentiality
of
electronic
records
from
the
point
of
their
creation
to
the
point
of
their
receipt.
Such
procedures
and
controls
shall
include
those
identified
in
§11.10,
as
appropriate,
and
additional
measures
such
as
document
encryption
and
use
of
appropriate
digital
signature
standards
to
ensure,
as
necessary
under
the
circumstances,
record
authenticity,
integrity,
and
confidentiality.
B
§11.50
Signature
manifestations.
11.50
(a)
Signed
electronic
records
shall
contain
information
associated
with
the
signing
that
clearly
indicates
all
of
the
following:
(1)
The
printed
name
of
the
signer;
(2)
The
date
and
time
when
the
signature
was
executed;
and
(3)
The
meaning
(such
as
review,
approval,
responsibility,
or
authorship)
associated
with
the
signature.
11.50
(b)
The
items
identified
in
paragraphs
(a)(1),
(a)(2),
and
(a)(3)
of
this
section
shall
be
subject
to
the
same
controls
as
for
electronic
records
and
shall
be
included
as
part
of
any
human
readable
form
of
the
electronic
record
(such
as
electronic
display
or
printout).
B
§11.70
Signature/record
linking.
Electronic
signatures
and
handwritten
signatures
executed
to
electronic
records
shall
be
linked
to
their
respective
electronic
records
to
ensure
that
the
signatures
cannot
be
excised,
copied,
or
otherwise
transferred
to
falsify
an
electronic
record
by
ordinary
means.
Subpart
C
Electronic
signatures
C
§11.100
General
requirements.
11.100
(a)
Each
electronic
signature
shall
be
unique
to
one
individual
and
shall
not
be
reused
by,
or
reassigned
to,
anyone
else.
11.100
(b)
Before
an
organization
establishes,
assigns,
certifies,
or
otherwise
sanctions
an
individual's
electronic
signature,
or
any
element
of
such
electronic
signature,
the
organization
shall
verify
the
identity
of
the
individual.
11.100
(c)
Persons
using
electronic
signatures
shall,
prior
to
or
at
the
time
of
such
use,
certify
to
the
agency
that
the
electronic
signatures
in
their
system,
used
on
or
after
August
20,
1997,
are
intended
to
be
the
legally
binding
equivalent
of
traditional
handwritten
signatures.
(1)
The
certification
shall
be
submitted
in
paper
form
and
signed
with
a
traditional
handwritten
signature,
to
the
Office
of
Regional
Operations
(HFC-100),
5600
Fishers
Lane,
Rockville,
MD
20857,0
(2)
Persons
using
electronic
signatures
shall,
upon
agency
request
provide
additional
certification
or
testimony
that
a
specific
electronic
signature
is
the
legally
binding
equivalent
of
the
signer's
handwritten
signature.
C
§11.200
Electronic
signature
components
and
controls.
11.200
(a)
Electronic
signatures
that
are
not
based
upon
biometrics
shall
(1)
Employ
at
least
two
distinct
identification
components
such
as
an
identification
code
and
password.
11.200
(a)(1)(i)
When
an
individual
executes
a
series
of
signings
during
a
single,
continuous
period
of
controlled
system
access,
the
firs
signing
shall
be
executed
using
all
electronic
signature
components;
subsequent
signings
shall
be
executed
using
at
least
one
electronic
signature
component
that
is
only
executable
by,
and
designed
to
be
used
only
by,
the
individual.
11.200
(a)(1)(ii)
When
an
individual
executes
one
or
more
signings
not
performed
during
a
single,
continuous
period
of
controlled
system
access,
each
signing
shall
be
executed
using
all
of
the
electronic
signature
components.
11.200
(a)(2)
Electronic
signatures
that
are
not
based
upon
biometrics
shall
be
used
only
by
their
genuine
owners.
11.200
(a)(3)
Be
administered
and
executed
to
ensure
that
attempted
use
of
an
individual's
electronic
signature
by
anyone
other
than
its
genuine
owner
requires
collaboration
of
two
or
more
individuals.
11.200
(b)
Electronic
signatures
based
upon
biometrics
shall
be
designed
to
ensure
that
they
cannot
be
used
by
anyone
other
than
their
genuine
owners.
C
§11.300
Controls
for
identification
codes/passwords.
Persons
who
use
electronic
signatures
based
upon
use
of
identification
codes
in
combination
with
passwords
shall
employ
controls
to
ensure
their
security
and
integrity.
Such
controls
shall
include:
11.300
(a)
Maintaining
the
uniqueness
of
each
combined
identification
code
and
password,
such
that
no
two
individuals
have
the
same
combination
of
identification
code
and
password.
11.300
(b)
Ensuring
that
identification
code
and
password
issuances
are
periodically
checked,
recalled,
or
revised
(e.g.,
to
cover
such
events
as
password
aging).
11.300
(c)
Following
loss
management
procedures
to
electronically
deauthorize
lost,
stolen,
missing,
or
otherwise
potentially
compromised
tokens,
cards,
and
other
devices
that
bear
or
generate
identification
code
or
password
information,
and
to
issue
temporary
or
permanent
replacements
using
suitable,
rigorous
controls.
11.300
(d)
Use
of
transaction
safeguards
to
prevent
unauthorized
use
of
passwords
and/or
identification
codes,
and
to
detect
and
report
in
an
immediate
and
urgent
manner
any
attempts
at
their
unauthorized
use
to
the
system
security
unit,
and,
as
appropriate,
to
organizational
management.
11.300
(e)
Initial
and
periodic
testing
of
devices,
such
as
tokens
or
cards,
that
bear
or
generate
identification
code
or
password
information
to
ensure
that
they
function
properly
and
have
not
been
altered
in
an
unauthorized
manner.
English (Original Text)
A General Provisions
§ 11.1 Scope.
(a) The regulations in this part set
forth the criteria under which the
agency considers electronic records,
electronic signatures, and handwritten
signatures executed to electronic
records to be trustworthy, reliable, and
generally equivalent to paper records
and handwritten signatures executed on paper.
(b) This part applies to records in
electronic form that are created,
modified, maintained, archived,
retrieved, or transmitted, under any
records requirements set forth in agency
regulations. This part also applies to electronic
records submitted to the agency under
requirements of the Federal Food, Drug, and
Cosmetic Act and the Public Health Service Act,
even if such records are not specifically
identified in agency regulations.
However, this part does not apply to
paper records that are, or have been,
transmitted by electronic means.
(c) Where electronic signatures and
their associated electronic records meet the
requirements of this part, the agency will consider
the electronic signatures to be equivalent to full
handwritten signatures, initials, and other general
signings as required by agency regulations, unless
specifically excepted by regulation(s) effective on
or after august 20, 1997.
(d) Electronic records that meet the
requirements of this part may be used in lieu of
paper records, in accordance
with § 11.2, unless paper records are
specifically required.
(e) Computer systems (including
hardware and software), controls, and
attendant documentation maintained
under this part shall be readily available
for, and subject to, FDA inspection.
§ 11.2 Implementation
(a) For records required to be
maintained but not submitted to the
agency, persons may use electronic
records in lieu of paper records or
electronic signatures in lieu of
traditional signatures, in whole or in
part, provided that the requirements of
this part are met.
(b) For records submitted to the
agency, persons may use electronic
records in lieu of paper records or
electronic signatures in lieu of
traditional signatures, in whole or in
part, provided that:
(1) The requirements of this part are
met; and
(2) The document or parts of a
document to be submitted have been
identified in public docket No. 92S–
0251 as being the type of submission the agency
accepts in electronic form. This docket will identify
specifically what types of documents or parts of
documents are acceptable for
submission in electronic form without
paper records and the agency receiving
unit(s) (e.g., specific center, office,
division, branch) to which such
submissions may be made. Documents
to agency receiving unit(s) not specified
in the public docket will not be
considered as official if they are
submitted in electronic form; paper
forms of such documents will be
considered as official and must
accompany any electronic records.
Persons are expected to consult with the intended
agency receiving unit for
details on how (e.g., method of
transmission, media, file formats, and
technical protocols) and whether to
proceed with the electronic submission.
§ 11.3 Definitions.
(a) The definitions and interpretations
of terms contained in section 201 of the
act apply to those terms when used in
this part.
(b) The following definitions of terms
also apply to this part:
(1) Act means the Federal Food, Drug,
and Cosmetic Act (secs. 201–903 (21
U.S.C. 321–393)).
(2) Agency means the Food and Drug
Administration.
(3) Biometrics means a method of
verifying an individual’s identity based
on measurement of the individual’s
physical feature(s) or repeatable
action(s) where those features and/or
actions are both unique to that
individual and measurable.
(4) Closed system means an
environment in which system access is
controlled by persons who are
responsible for the content of electronic
records that are on the system.
(5) Digital signature means an
electronic signature based upon
cryptographic methods of originator
authentication, computed by using a set
of rules and a set of parameters such
that the identity of the signer and the
integrity of the data can be verified.
(6) Electronic record means any
combination of text, graphics, data,
audio, pictorial, or other information
representation in digital form that is
created, modified, maintained, archived, retrieved,
or distributed by a computer system.
(7) Electronic signature means a
computer data compilation of any
symbol or series of symbols executed,
adopted, or authorized by an individual
to be the legally binding equivalent of
the individual’s handwritten signature.
(8) Handwritten signature means the
scripted name or legal mark of an
individual handwritten by that
individual and executed or adopted
with the present intention to
authenticate a writing in a permanent
form. The act of signing with a writing
or marking instrument such as a pen or
stylus is preserved. The scripted name
or legal mark, while conventionally
applied to paper, may also be applied to other
devices that capture the name or mark.
(9) Open system means an environment in which
system access is
not controlled by persons who are
responsible for the content of electronic
records that are on the system.
Subpart B Electronic Records
B §11.10 Controls for closed systems.
Persons who use closed systems to create,
modify, maintain, or transmit electronic records
shall employ procedures and controls designed to
ensure the authenticity, integrity, and, when
appropriate, the confidentiality of electronic
records, and to ensure that the signer cannot
readily repudiate the signed record as not
genuine. Such procedures and controls shall
include the following:
11.10 (a) Validation of systems to ensure
accuracy, reliability, consistent intended
performance, and the ability to discern invalid or
altered records.
11.10 (b) The ability to generate accurate and
complete copies of records in both human
readable and electronic form suitable for
inspection, review, and copying by the agency.
Persons should contact the agency if there are
any questions regarding the ability of the agency
to perform such review and copying of the
electronic records.
11.10 (c) Protection of records to enable their
accurate and ready retrieval throughout the
records retention period
11.10 (d) Limiting system access to authorized
individuals.
11.10 (e) Use of secure, computer-generated,
time-stamped audit trails to independently record
the date and time of operator entries and
actions that create, modify, or delete electronic
records. Record changes shall not obscure
previously recorded information.
Such audit trail documentation shall be retained
for a period at least as long as that required for the
subject electronic records
and shall be available for agency review and
copying.
11.10 (f) Use of operational system checks to
enforce permitted sequencing of steps and events,
as appropriate.
11.10 (g) Use of authority checks to ensure that
only authorized individuals can use the system,
electronically sign a record, access the operation
or computer system input or output device, alter a
record, or perform the operation at hand.
11.10 (h) Use of device (e.g., terminal) checks to
determine, as appropriate, the validity of the
source of data input or operational instruction.
11.10 (i) Determination that persons who develop,
maintain, or use electronic record/electronic
signature systems have the education,
training, and experience to perform their assigned
tasks.
11.10 (j) The establishment of, and adherence to,
written policies that hold individuals accountable
and responsible for actions initiated under their
electronic signatures, in order to deter record and
signature falsification.
11.10 (k) Use of appropriate controls over systems
documentation including:
(1) Adequate controls over the distribution of,
access to, and use of documentation for system
operation and maintenance.
(2) Revision and change control procedures to
maintain an audit trail that documents time-
sequenced development and modification of
systems documentation.
B §11.30 Controls for open systems.
Persons who use open systems to create, modify,
maintain, or transmit electronic records shall
employ procedures and controls designed to
ensure the authenticity, integrity, and, as
appropriate, the confidentiality of electronic
records from the point of their creation to the point
of their receipt. Such procedures and controls
shall include those identified in §11.10, as
appropriate, and additional measures such as
document encryption and use of appropriate
digital signature standards to ensure, as
necessary under the circumstances, record
authenticity, integrity, and confidentiality.
B §11.50 Signature manifestations.
11.50 (a) Signed electronic records shall contain
information associated with the signing that clearly
indicates all of the following:
(1) The printed name of the signer;
(2) The date and time when the signature was
executed; and
(3) The meaning (such as review, approval,
responsibility, or authorship) associated with the
signature.
11.50 (b) The items identified in paragraphs (a)(1),
(a)(2), and (a)(3) of this section shall be subject to
the same controls as for electronic records and
shall be included as part of any human readable
form of the electronic record (such as electronic
display or printout).
B §11.70 Signature/record linking.
Electronic signatures and handwritten signatures
executed to electronic records shall be linked to
their respective electronic records to ensure that
the signatures cannot be excised, copied, or
otherwise transferred to falsify an electronic record
by ordinary means.
Subpart C Electronic signatures
C §11.100 General requirements.
11.100 (a) Each electronic signature shall be
unique to one individual and shall not be reused
by, or reassigned to, anyone else.
11.100 (b) Before an organization establishes,
assigns, certifies, or otherwise sanctions an
individual's electronic signature, or any element of
such electronic signature, the organization shall
verify the identity of the individual.
11.100 (c) Persons using electronic signatures
shall, prior to or at the time of such use, certify to
the agency that the electronic signatures in their
system, used on or after August 20, 1997, are
intended to be the legally binding equivalent of
traditional handwritten signatures.
(1) The certification shall be submitted in paper
form and signed with a traditional handwritten
signature, to the Office of Regional Operations
(HFC-100), 5600 Fishers Lane, Rockville, MD
20857,0
(2) Persons using electronic signatures shall, upon
agency request provide additional certification or
testimony that a specific electronic signature is the
legally binding equivalent of the signer's
handwritten signature.
C §11.200 Electronic signature components
and controls.
11.200 (a) Electronic signatures that are not
based upon biometrics shall
(1) Employ at least two distinct identification
components such as an identification code and
password.
11.200 (a)(1)(i) When an individual executes a
series of signings during a single, continuous
period of controlled system access, the firs
signing shall be executed using all electronic
signature components; subsequent signings shall
be executed using at least one electronic
signature component that is only executable by,
and designed to be used only by, the individual.
11.200 (a)(1)(ii) When an individual executes one
or more signings not performed during a single,
continuous period of controlled system access,
each signing shall be executed using all of the
electronic signature components.
11.200 (a)(2) Electronic signatures that are not
based upon biometrics shall be used only by their
genuine owners.
11.200 (a)(3) Be administered and executed to
ensure that attempted use of an individual's
electronic signature by anyone other than its
genuine owner requires collaboration of two or
more individuals.
11.200 (b) Electronic signatures based upon
biometrics shall be designed to ensure that they
cannot be used by anyone other than their
genuine owners.
C §11.300 Controls for identification
codes/passwords.
Persons who use electronic signatures based
upon use of identification codes in combination
with passwords shall employ controls to ensure
their security and integrity. Such controls shall
include:
11.300 (a) Maintaining the uniqueness of each
combined identification code and password, such
that no two individuals have the same combination
of identification code and password.
11.300 (b) Ensuring that identification code and
password issuances are periodically checked,
recalled, or revised (e.g., to cover such events as
password aging).
11.300 (c) Following loss management
procedures to electronically deauthorize lost,
stolen, missing, or otherwise potentially
compromised tokens, cards, and other devices
that bear or generate identification code or
password information, and to issue temporary or
permanent replacements using suitable, rigorous
controls.
11.300 (d) Use of transaction safeguards to
prevent unauthorized use of passwords and/or
identification codes, and to detect and report in an
immediate and urgent manner any attempts at
their unauthorized use to the system security unit,
and, as appropriate, to organizational
management.
11.300 (e) Initial and periodic testing of devices,
such as tokens or cards, that bear or generate
identification code or password information to
ensure that they function properly and have not
been altered in an unauthorized manner.