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### PDF Reference, Sixth Edition, version 1.7

The ISO 32000-1 standard now available from ISO, preserves the technical integrity of the Adobe PDF 1.7 Reference and is vendor neutral, more precise, and conforms to ISO conventions. The ISO 32000-1 document represents a complete expression of the PDF standard and is now the definitive reference.

This document describes PDF features supported in the Adobe® Acrobat® 8.1 and LiveCycle ES 8.2 family of products but not reflected in the Adobe PDF 1.7 Reference. The PDF specification is represented by the combination of this document, the PDF Reference, sixth edition, version 1.7 (Nov. 2006), Errata to Sixth Edition and the PDF Redaction: Addendum to the PDF Reference, sixth edition, version 1.7. Adobe has submitted these features to ISO for possible inclusion in the next revision to ISO 32000.

This book provides a description of the PDF file format and is intended primarily for developers of PDF producer applications that create PDF files directly. It also contains enough information to allow developers to write PDF consumer applications that read existing PDF files and interpret or modify their contents.

(Updated Oct. 23, 2007)

(Nov 2006)
Provides additional information about redaction annotation types.

### PDF Reference, Fifth Edition, version 1.6

(Nov 2004)

(Updated Oct. 4, 2006)

(Jan. 23, 2006)
Provides additional information about blend modes for PDF transparency.

### PDF Reference, Fourth Edition, version 1.5

(Aug 2003)
This file has been compressed using Acrobat 6.0 compression for faster download. It requires Acrobat or Adobe Reader 6.0 software to open.

(Aug 2003)
The same document is available in uncompressed form, readable by Acrobat 5.0 and later versions.

(Revised Oct. 29, 2004)

### PDF Reference, Third Edition, version 1.4

(Nov 2001)

(Revised Jun 2003)

(Jul 3, 2000)