ISO 15930-9:2020

INTERNATIONAL ISO
STANDARD 15930-9
First edition
2020-11
Graphic technology — Prepress digital
data exchange using PDF —
Part 9:
Complete exchange of printing data
(PDF/X-6) and partial exchange of
printing data with external profile
reference (PDF/X-6p and PDF/X-6n)
using PDF 2.0
Technologie graphique — Échange de données numériques de
préimpression utilisant le PDF —
Partie 9: Échange complet de données d’impression (PDF/X-6) et
échange partiel de données d’impression avec une référence de profil
externe (PDF/X-6p) utilisant le PDF 2.0
Reference number
©
ISO 2020
© ISO 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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ii © ISO 2020 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Notations. 3
5 PDF/X-6 conforming files and processors . 3
6 Technical requirements . 4
6.1 General . 4
6.2 Print and non-print elements . 4
6.2.1 General. 4
6.2.2 Print elements . 4
6.2.3 Non-print elements . 4
6.3 Intended visual appearance . 5
6.4 Complete exchange . 5
6.5 File structure . 5
6.5.1 File header . 5
6.5.2 File trailer . . . 6
6.5.3 Cross reference table . 6
6.5.4 Stream objects . 6
6.5.5 Name objects . 6
6.5.6 Permissions . 7
6.5.7 Document catalog dictionary . 7
6.6 Colour . 7
6.6.1 General. 7
6.6.2 Identification of characterized printing condition . 7
6.6.3 Print element colour spaces . .10
6.7 Graphics .11
6.7.1 Content streams.11
6.7.2 Use of transparency . .12
6.7.3 Extended graphics state.12
6.7.4 Images .13
6.7.5 XObjects .14
6.8 Fonts .14
6.8.1 General.14
6.8.2 Embedded fonts .14
6.8.3 Use of .notdef glyph .15
6.8.4 Font metrics .15
6.8.5 Character encodings .15
6.9 Bounding boxes .15
6.10 Trapping.16
6.11 Metadata and document identification .16
6.11.1 General.16
6.11.2 Namespaces and prefixes .16
6.11.3 Version and conformance level identification .17
6.11.4 File identifiers .17
6.11.5 File provenance information .17
6.12 Annotations.18
6.12.1 General.18
6.12.2 Annotation dictionaries .18
6.12.3 Annotation appearances .18
6.13 Interactive forms .18
6.13.1 General.18
6.13.2 XFA forms .19
6.13.3 Digital signatures . .19
6.14 Actions .19
6.14.1 General.19
6.14.2 Handling of JavaScript actions .19
6.14.3 Trigger events .19
6.14.4 Handling of GoToR, GoToE, URI and SubmitForm actions .19
6.15 Use of optional content .20
6.16 Viewer preferences .21
6.17 Use of alternate presentations .21
6.18 Document requirements .21
6.19 Spectral Data (CxF) .21
Annex A (normative) Requirements for PDF/X-6p .22
Annex B (normative) Requirements for PDF/X-6n .24
Bibliography .26
iv © ISO 2020 – All rights reserved

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 130, Graphic technology.
A list of all parts in the ISO 15930 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
Introduction
ISO 15930 (all parts) defines methods for the exchange of digital data within the graphic arts industry
and for the exchange of files between graphic arts establishments. It is a multi-part document where
each part is intended to respond to different workflow requirements. These workflows differ in the
degree of flexibility required. However, increasing flexibility can lead to the possibility of uncertainty or
error. The goal throughout the various parts of ISO 15930 has been to maintain the degree of flexibility
required while minimizing the uncertainty.
Many printed documents are assemblies of partial pages and/or pages created at different locations
and by different organizations. The merging of these individual elements into the final printing form
and the subsequent printing can take place at different locations. Some of these elements can also be
routed to multiple sites for incorporation into other documents. Each of these elements is referred to in
ISO 15930 as a compound entity.
A variety of data formats and structures are used for the creation of this type of material, but with
two prevalent kinds of underlying data structures. These are vector-based data for the encoding of
line art and textual information and raster-based data for the encoding of image information, including
previously rasterized line art and textual information.
Both kinds of data structures are required along with page description information in an open
electronic workflow. The subject of ISO 15930 is a format for the exchange of object-based data where
individual objects can be in either vector or raster data structures.
The various parts of ISO 15930 define a number of conformance levels intended to address different
requirements; all define data formats and their usage to permit the predictable dissemination of a
compound entity to one or more locations. These goals are accomplished by defining a specific use of
the Portable Document Format (PDF). In order to achieve a level of exchange that avoids any ambiguity
in interpretation of the file, a limited set of PDF objects that are permitted to be used is identified and
restrictions to the use, or form of use, of those objects, and/or keys within those objects are added.
In some environments, the data exchange needs to be in a form ready for final print reproduction,
by transfer of a single file. This file contains all the content information necessary to process and
render the document, as intended by the sender, coded inside a single PDF file. No other files, neither
external files nor internally embedded files, are required or permitted. This exchange requires no prior
knowledge of the sending and receiving environments and is sometimes referred to as “complete” or
“blind” exchange. It is platform- and transport-independent. Whereas many production workflows
benefit from the exchange of complete material, with all elements present, there are circumstances
when this is not appropriate. In certain workflows, some or all of the referenced elements might be
more logically present at the receiving site, or might be exchanged at a different time. These include
high-resolution contone-image files, line-art files, ICC profiles, etc. These exchanges will generally
require prior agreement between sender and receiver.
Historically, the exchange needed to be restricted to gray, CMYK (and spot colour) data. In modern
workflows, it is more appropriate to convey it as colour-managed, CMYK, gray, RGB, and/or spot colour,
or to use alternative process colour models.
Several new versions of the PDF specification have been issued since the publication of ISO 15930-1 in
2001. More recent parts of ISO 15930 expand and extend earlier parts by reference to later versions of
the PDF specification.
Table 1 summarizes the conformance levels defined in each part of ISO 15930.
vi © ISO 2020 – All rights reserved

Table 1 — PDF/X conformance levels
Conformance ISO 15930 Complete Colour-managed Print PDF version
level part number exchange data permitted characterization
spaces supported
PDF/X-1:2001 ISO 15930-1 Yes No CMYK 1.3
PDF/X-1a:2001 ISO 15930-1 Yes No CMYK 1.3
PDF/X-1a:2003 ISO 15930-4 Yes No CMYK 1.4
PDF/X-3:2002 ISO 15930-3 Yes Yes Gray, RGB, CMYK 1.3
PDF/X-3:2003 ISO 15930-6 Yes Yes Gray, RGB, CMYK 1.4
PDF/X-4 ISO 15930-7 Yes Yes Gray, RGB, CMYK 1.6
PDF/X-4p ISO 15930-7 No Yes Gray, RGB, CMYK 1.6
PDF/X-5g ISO 15930-8 No Yes Gray, RGB, CMYK 1.6
PDF/X-5n ISO 15930-8 No Yes n-colourant 1.6
PDF/X-5pg ISO 15930-8 No Yes Gray, RGB, CMYK 1.6
PDF/X-6 ISO 15930-9 Yes Yes Gray, RGB, CMYK 2.0
PDF/X-6p ISO 15930-9 No Yes Gray, RGB, CMYK 2.0
PDF/X-6n ISO 15930-9 No Yes n-colourant 2.0
This document specifies the PDF/X-6 conformance level, which incorporates all of the features available
in the PDF/X-1a, PDF/X-3 and PDF/X-4 conformance levels defined in ISO 15930-1, ISO 15930-3,
ISO 15930-4, ISO 15930-6, ISO 15930-7 and adds the following.
— The referenced version is PDF 2.0 and therefore supports the additions to the PDF language found
there, as modified by this document.
— Annotations, including digital signatures, form fields and videos, are allowed in the printable area
of a page.
This document also specifies the PDF/X-6p and PDF/X-6n conformance levels. PDF/X-6 requires that
any ICC profile describing the characterization of the printing condition for which a file was prepared be
embedded. PDF/X-6p and PDF/X-6n allow these Output Intent ICC profiles to be maintained externally
to the exchanged file; the difference being that the profile for PDF/X-6n specifies n-colourants instead
of only Gray, RGB or CMYK. This is especially useful in those situations where the size of the ICC profile
is large in comparison with the size of the file to be exchanged; where there are a very large number
of files to be exchanged that have been prepared for the same printing condition, tone and gamut
compression and black generation; or where there are licensing issues that preclude embedding.
Due consideration needs to be given to the increased potential for issues requiring technical discussion
between file submitters and receivers when determining whether to use the PDF/X-6p or PDF/X-6n
conformance levels in preference to PDF/X-6. In addition, it is likely that a larger proportion of receiving
sites will be capable of accepting and correctly processing PDF/X-6 files. PDF/X-6 is preferred to PDF/
X-6p or PDF/X-6n where there is no significant benefit in the use of the latter.
It is anticipated that a variety of products will be developed based on PDF/X, such as readers (including
viewers) and writers of PDF/X files, and products that offer combinations of these features. Different
products will incorporate various capabilities to prepare, interpret and process conforming files
based on the application needs as perceived by the suppliers of the products. A conforming processor
of this document is only required to be able to read and appropriately process all files conforming to
the specified conformance levels within this document. Of course, a conforming processor can support
other PDF standards, be they parts of ISO 15930 or not, but it is not required.
All parts of ISO 15930 define requirements and restrictions on the process of rendering PDF/X files
for viewing and print, in addition to the requirements and restrictions of elements and structures
within the files themselves. In some circumstances, it might be appropriate to render files without rigid
adherence to the provisions of ISO 15930, but it is important to be aware that such renderings do not
conform to PDF/X.
Users of this document are cautioned that they are expected to be familiar with the documents listed as
normative references and the terms used within those documents. This document prescribes specific
uses of, and limitations on the use of, ISO 32000-2 (PDF 2.0) and its associated supporting documents.
An ongoing series of Application Notes is maintained for the guidance of developers and users of the
PDF/X family of International Standards. These application notes, and other documents relevant to
PDF/X, are available from APTech, The Association for PRINT Technologies, in the APTech, Standards
Workroom at .
A number of other International Standards, defining focussed subsets of the Portable Document Format
in areas other than the graphic arts, are either published or under development, including PDF/A, and
PDF/UA. Where possible, PDF/X has been designed to allow a single file to comply both with PDF/X
and with these other standards. The PDF/VT standards for variable data printing require that all
conforming PDF/VT files are also conforming PDF/X files.
viii © ISO 2020 – All rights reserved

INTERNATIONAL STANDARD ISO 15930-9:2020(E)
Graphic technology — Prepress digital data exchange
using PDF —
Part 9:
Complete exchange of printing data (PDF/X-6) and partial
exchange of printing data with external profile reference
(PDF/X-6p and PDF/X-6n) using PDF 2.0
1 Scope
This document specifies the use of ISO 32000-2 (PDF 2.0) for the complete and partial exchange of
digital data intended for print reproduction.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 15076-1:2010, Image technology colour management — Architecture, profile format and data
structure — Part 1: Based on ICC.1:2010
1)
ISO 32000-2:— , Document management — Portable document format — PDF 2.0
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
characterized printing condition
printing condition for which process control aims are defined and for which the relationship between
input data and the colorimetry of the printed image is documented
Note 1 to entry: It is generally preferable that the process control aims of the printing condition and the
associated characterization data be made publicly available via the accredited standards process or industry
trade associations.
3.2
CMYK
subtractive process colour model where the channels are called Cyan, Magenta, Yellow and Black
1) Under preparation. Stage at the time of publication: ISO/FDIS 32000-2:2020.
3.3
compound entity
unit of work with all text, graphics and image elements prepared for final print reproduction that might
represent a single page for printing, a portion of a page or a combination of pages
3.4
conformance level
identified set of restrictions and requirements with which files, processors and writers are required
to comply
3.5
default colour space
PDF colour space named DefaultGray, DefaultRGB or DefaultCMYK that provides an indirect method of
specifying the colour space of elements
3.6
element
substructure of a compound entity relative to the current processing environment, such as a block of
text, a contone picture or an outline graphic that, by itself, comprises the smallest logical composed unit
of a compound entity
3.7
n-colourant
process colour model other than gray, RGB (3.12) or CMYK (3.2), and comprising at least two colourants
3.8
non-print element
element (3.6) not intended for final print reproduction
3.9
print element
element (3.6) intended for final print reproduction
3.10
process colourant
additive or subtractive colourant whose characteristics (colour, transparency, etc.) make it suitable to
combine with other colourants to form secondary or tertiary colours
3.11
process colour model
colours, defined in a colour coordinate system, produced by a set of process colourants (3.10)
3.12
RGB
additive process colour model (3.11) where the channels are called Red, Green and Blue
3.13
spot colour
single colourant, identified by name, whose values are specified independently from the colour values
specified in a colour coordinate system
3.14
trapping
modification of boundaries of colour areas to account for dimensional variations in the printing process
by overprinting in selected colours at the boundaries between colours that might inadvertently be left
uncoloured due to normal variations of printing registration
Note 1 to entry: Trapping is sometimes referred to as chokes and spreads or grips. This is not the same as ink
trapping.
2 © ISO 2020 – All rights reserved

4 Notations
PDF operators, PDF keywords, the names of keys in PDF dictionaries, and other predefined names are
written in bold sans serif font; operands of PDF operators or values of dictionary keys are written in
italic font. Some names can also be used as values, depending on the context, and so the styling of the
content will be context specific.
EXAMPLE 1 The Default value for the TR2 key.
Token characters used to delimit objects and describe the structure of PDF files, as defined in
ISO 32000-2:—, 7.2.1, may be identified by their ISO/IEC 646 character name written in upper case in
bold font followed by a parenthetic two digit hexadecimal character value with the suffix “h”.
EXAMPLE 2 CARRIAGE RETURN (0Dh).
Text string characters, as defined by ISO 32000-2:—, 7.9.2, may be identified by their ISO/IEC 10646
character name written in uppercase in bold sans serif font followed by a parenthetic four digit
hexadecimal character code value with the prefix “U+”.
EXAMPLE 3 EN SPACE (U+2002).
5 PDF/X-6 conforming files and processors
This document specifies the use of the PDF file format for the exchange of digital data representing a
compound entity. Specific requirements for conformance with PDF/X-6p are given in Annex A. Specific
requirements for conformance with PDF/X-6n are given in Annex B.
A PDF/X-6 conforming file is a PDF file in which those features necessary for the exchange of a compound
entity are in accordance with this document. A PDF/X-6 conforming file may also include other valid
PDF features that do not affect final print reproduction of the compound entity.
The proper mechanism by which a file can presumptively identify itself as being a PDF/X-6 file is
described in 6.11.3.
Conforming PDF/X-6 files shall adhere to all requirements of ISO 32000-2 as modified by this
document. A conforming file may include any valid ISO 32000-2 feature that is not explicitly forbidden
by this document. Features described in PDF specifications prior to Version 2.0, which are not explicitly
described in ISO 32000-2, should not be used.
NOTE A conforming file is not obligated to use any PDF feature other than those explicitly required by
ISO 32000-2 or this document.
A PDF/X-6 conforming writer is a software application that is able to write files in accordance with the
requirements of the PDF/X-6 conformance level specified in document.
A PDF/X-6 conforming processor is a software application that is able to read and appropriately process,
according to the rules defined in this document, all files conforming to the requirements for PDF/X-6
files as defined in this document.
A conforming processor shall comply with all applicable requirements regarding processor functional
behaviour specified in this document. The requirements of this document with respect to processor
behaviour are stated in terms of general functional requirements applicable to all conforming
processors. This document does not prescribe any specific technical design, user interface or
implementation details of conforming processors.
The rendering and other processing of conforming files shall be performed as defined in ISO 32000-2
subject to the additional restrictions specified by this document.
To the extent that ISO 32000-2 and this document permit more than one rendering of a conforming file,
a conforming processor may use embedded job ticket or metadata information to control the rendering
of the file more precisely.
EXAMPLE 1 (Trapping) If a PDF/X-6 conforming file specifies p df : T rapp e d =Fa lse, a conforming processor
might use job ticket information to determine details of how the file is to be trapped. If the file specifies pdf:
Trapped =Tr ue, a conforming processor might ignore any trapping information in an embedded job ticket.
EXAMPLE 2 (Screening) A PDF/X-6 conforming processor can use embedded job ticket information to
determine the screening to be used to render the file. A PDF/X-6 conforming processor can ignore screening
information in the PDF/X-6 file. A conforming processor might use screening data from the PDF/X-6 file, from the
job ticket, or from local system defaults.
EXAMPLE 3 (Print product metadata) A PDF/X-6 conforming processor can look for the presence of
[7]
information that complies with ISO 21812-1 to determine if there is any print product metadata that would
influence the production of the file. A PDF/X-6 conforming can ignore any additional information in the PDF/X-6
file, not mentioned in this document.
6 Technical requirements
6.1 General
PDF/X-6 is a restricted subset of PDF 2.0, as defined in ISO 32000-2. The features of PDF that shall be
required, prohibited or restricted are specified in 6.2 to 6.16 inclusively. These features shall be used as
prescribed in ISO 32000-2 and as further restricted by this document. Any feature in ISO 32000-2 that
is marked as deprecated should not appear in a PDF/X-6 file, but a conforming processor shall process
the file as if the features were not present.
6.2 Print and non-print elements
6.2.1 General
A PDF/X-6 conforming file may contain two classes of elements:
a) those intended for final print reproduction (print elements);
b) those not intended for final print reproduction (non-print elements).
6.2.2 Print elements
Except as specified below, print elements are those drawn or referenced (directly or indirectly), using
keys and values defined in ISO 32000-2, from:
— the Contents stream(s) of Page objects; or
— the appearance stream of any annotation, including those with a Subtype value of Widget (form
fields), which has its printable flag set and its invisible and hidden flags clear (see ISO 32000-2:—,
12.5.3).
All optional content that would be regarded as print elements if not contained in an optional content
group shall be regarded as print elements, whether rendered in a specific instance or not.
Image XObjects that are only referenced from within the Alternates array of an Image XObject are non-
print elements.
6.2.3 Non-print elements
All elements within the file, which are not characterized as print elements, shall be considered non-
print elements.
4 © ISO 2020 – All rights reserved

Non-print elements may make use of any PDF feature that does not affect the rendered appearance of
print elements.
The requirements of Clause 6 shall not apply to non-print elements, or to any resources referenced
exclusively by such elements.
This includes allowing non-print elements to make use of any PDF colour space thus making the
provisions of 6.6.2 and 6.6.3 no longer apply to non-print elements.
6.3 Intended visual appearance
A PDF/X-6 conforming file is created such that each page has a specific intended visual appearance.
Where a PDF/X-6 file is printed or viewed on a system that differs from that intended by the creator, the
PDF/X-6 conforming processor should reproduce that intended visual appearance as closely as possible.
NOTE 1 For example, if the gamut of the viewing device does not contain the whole output intent gamut, an
alert can be visually noticed.
This applies to presentation on a screen, to production printing and to hard- and soft-proofing that
predicts production print.
NOTE 2 Examples of such systems are those where the device colour space does not match that identified
in the output intent (see 6.6.2.1), or where spot-colour separations specified in Separation or DeviceN colour
spaces are printed using process colourants (see 6.6.3.4).
NOTE 3 Among other things, transformations between colour spaces affect colour reproduction, overprints,
trapping, transparency and smooth shading.
6.4 Complete exchange
All components of a compound entity intended for PDF/X-6-compliant complete exchange that affect
rendering shall be contained in the body of a single PDF/X-6 file.
In this context, “complete” means the exchanged files shall include:
— all PDF resources (as listed in ISO 32000-2) used in print elements, including all font programs &
encodings, and colour space resources, and
— all print elements, properly prepared for the characterized printing condition of the page(s) on
which they are displayed.
In order to achieve complete exchange, a pre-separated PDF file, as defined in ISO 32000-2:—, 14.11.4,
shall not be used.
6.5 File structure
6.5.1 File header
The file header shall begin at byte zero and shall consist of “%PDF-2.n” followed by a single EOL marker,
where ‘n’ is a single digit number between 0 (30h) and 9 (39h).
NOTE 1 This clarifies the requirement in ISO 32000-2:—, 7.5.2
The aforementioned EOL marker shall be immediately followed by a % (25h) character followed by at
least four bytes, each of whose encoded byte values shall have a decimal value greater than 127.
NOTE 2 The presence of encoded byte values greater than decimal 127 near the beginning of a file is used by
various software tools and protocols to classify the file as containing 8-bit binary data that needs to be preserved
during processing.
6.5.2 File trailer
The Encrypt key shall not be present in the trailer dictionary.
NOTE The explicit prohibition of the Encrypt keyword has the implicit effect of disallowing encryption and
password-protected access permissions.
The Info key shall not be present in the trailer dictionary of PDF/X-6 conforming files unless there
exists a PieceInfo entry in the document catalog dictionary. If a document information dictionary is
present, it shall only contain a ModDate entry.
6.5.3 Cross reference table
The xref keyword and the cross reference subsection header shall be separated by a single EOL marker.
Any indirect object whose offset is not referenced in any cross-reference table nor in any cross-
reference stream shall be exempt from all requirements of this document and may be ignored by a
conforming processor. If a conforming processor chooses not to ignore such indirect objects, they shall
never influence the way content is processed and rendered.
NOTE Such objects can be considered as non-print elements (6.2.3).
6.5.4 Stream objects
6.5.4.1 General
A stream dictionary shall not contain the F, FFilter, or FDecodeParams keys.
NOTE 1 These keys are used to point to data external to the file. The explicit prohibition of these keys has the
implicit effect of disallowing external content that can create external dependencies and complicate production
and print.
NOTE 2 Since an inline image dictionary is not a stream object, this provision allows the presence of the F key
in an inline image dictionary as the abbreviation for Filter.
6.5.4.2 Filters
All standard stream filters listed in ISO 32000-2:—, Table 6 may be used, with the exception of
LZWDecode. Filters that are not listed in ISO 32000-2:—, Table 6 shall not be used.
In addition, the Crypt filter shall not be used unless the value of the Name key in the decode parameters
dictionary is Identity.
NOTE The Crypt filter is used to apply encryption and access control to the file. Applying encryption means
that complete exchange is compromised as additional data (a password) is needed to process the file.
6.5.5 Name objects
Font names, names of colourants in Separation and DeviceN colour spaces, and structure type names -
after expansion of character sequences escaped with a NUMBER SIGN (23h), if any, shall be valid UTF-8
character sequences.
These requirements make the recommendations set out in ISO 32000-2:—, 7.3.5 normative.
All other name objects should adhere to these same restrictions.
6 © ISO 2020 – All rights reserved

6.5.6 Permissions
No keys other than UR3 and DocMDP shall be present in a permissions dictionary (ISO 32000-2:—,
Table 263).
NOTE These restrictions are present to ensure that functionality such as obsolete versions of the “User
Rights” dictionary do not appear in a document conforming to this document.
6.5.7 Document catalog dictionary
If the Version key is present in the document catalog dictionary, the first character in its value shall
be a 2 (32h) and the second character of its value shall be a PERIOD (2Eh) (decimal point). The third
character shall be a decimal digit. The number of characters of the value of the Version key shall be
exactly 3.
NOTE This clarifies the requirement in ISO 32000-2:—, 7.5.2
6.6 Colour
6.6.1 General
Print elements may be exchanged either as output device code values or as colorimetrically defined
data. However, both types of data, if present in print elements in a PDF/X-6 file, shall be prepared for
the file’s identified characterized printing condition from a PDF/X-6 output intent prior to exchange.
The characterized printing condition shall have one colour channel (grayscale), three colour channels
(RGB) or four colour channels (CMYK).
NOTE For the use of n-colourant characterized printing conditions in PDF/X, see the PDF/X-6n conformance
level, as specified in Annex B.
Colorimetrically-defined data shall be described either using an ICC profile in an ICCBased colour space
or using an equivalent mechanism, namely a CalGray, CalRGB or Lab colour space. Device code values
may be defined in DeviceRGB, DeviceCMYK, DeviceGray, Separation, and DeviceN colour spaces as
specified and restricted by 6.6.3.
6.6.2 Identification of characterized printing condition
6.6.2.1 Output intents
The characterized printing condition (i.e. the process colour model for the output device) for which
data have been prepared is identified by use of a PDF/X output intent. A PDF/X output intent is defined
as an output intent dictionary (ISO 32000-2:—, 14.11.5) which shall contain an S key whose value shall
be GTS_PDFX and a DestOutputProfile key whose value shall be a valid ICC profile stream.
The document shall contain either a document-level PDF/X output intent (present in the OutputIntents
array of the document catalog dictionary), or each page dictionary shall contain an OutputIntents
array whose value shall be an array containing a PDF/X output intent, representing a page-level PDF/X
output intent, or both. When a page-level PDF/X output intent is present, then it shall be considered the
current PDF/X output intent when processing that page, otherwise the document-level PDF/X output
intent shall be considered current.
A conforming processor shall use the current PDF/
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