diff --git a/INSTALL b/INSTALL
index 3efbe16..e203dd2 100644
--- a/INSTALL
+++ b/INSTALL
@@ -1,5 +1,5 @@
 
-Installing libpng version 1.4.21beta01 - December 30, 2016
+Installing libpng version 1.4.21beta01 - August 7, 2017
 
 On Unix/Linux and similar systems, you can simply type
 
diff --git a/LICENSE b/LICENSE
index 4ad7d55..70b59f3 100644
--- a/LICENSE
+++ b/LICENSE
@@ -10,7 +10,7 @@
 
 This code is released under the libpng license.
 
-libpng versions 1.0.7, July 1, 2000, through 1.4.21beta01, December 30, 2016, are
+libpng versions 1.0.7, July 1, 2000, through 1.4.21beta01, August 7, 2017, are
 Copyright (c) 2000-2002, 2004, 2006-2017 Glenn Randers-Pehrson, are
 derived from libpng-1.0.6, and are distributed according to the same
 disclaimer and license as libpng-1.0.6 with the following individuals
@@ -107,4 +107,4 @@
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-December 30, 2016
+August 7, 2017
diff --git a/README b/README
index 8a8b9ce..a251612 100644
--- a/README
+++ b/README
@@ -1,4 +1,4 @@
-README for libpng version 1.4.21beta01 - December 30, 2016 (shared library 14.0)
+README for libpng version 1.4.21beta01 - August 7, 2017 (shared library 14.0)
 See the note about version numbers near the top of png.h
 
 See INSTALL for instructions on how to install libpng.
diff --git a/libpng-1.4.21beta01.txt b/libpng-1.4.21beta01.txt
index 172e2db..f1302c2 100644
--- a/libpng-1.4.21beta01.txt
+++ b/libpng-1.4.21beta01.txt
@@ -1,6 +1,6 @@
 libpng.txt - A description on how to use and modify libpng
 
- libpng version 1.4.21beta01 - December 30, 2016
+ libpng version 1.4.21beta01 - August 7, 2017
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2014 Glenn Randers-Pehrson
@@ -11,7 +11,7 @@
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.4.21beta01 - December 30, 2016
+ libpng versions 0.97, January 1998, through 1.4.21beta01 - August 7, 2017
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2014 Glenn Randers-Pehrson
 
diff --git a/libpng.3 b/libpng.3
index 36e5d99..09d9590 100644
--- a/libpng.3
+++ b/libpng.3
@@ -1,4 +1,4 @@
-.TH LIBPNG 3 "December 30, 2016"
+.TH LIBPNG 3 "August 7, 2017"
 .SH NAME
 libpng \- Portable Network Graphics (PNG) Reference Library 1.4.21beta01
 .SH SYNOPSIS
@@ -444,7 +444,7 @@
 .SH LIBPNG.TXT
 libpng.txt - A description on how to use and modify libpng
 
- libpng version 1.4.21beta01 - December 30, 2016
+ libpng version 1.4.21beta01 - August 7, 2017
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2014 Glenn Randers-Pehrson
@@ -455,7 +455,7 @@
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.4.21beta01 - December 30, 2016
+ libpng versions 0.97, January 1998, through 1.4.21beta01 - August 7, 2017
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2014 Glenn Randers-Pehrson
 
@@ -3895,7 +3895,7 @@
 
 Thanks to Frank J. T. Wojcik for helping with the documentation.
 
-Libpng version 1.4.21beta01 - December 30, 2016:
+Libpng version 1.4.21beta01 - August 7, 2017:
 Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
 Currently maintained by Glenn Randers-Pehrson (glennrp at users.sourceforge.net).
 
@@ -3920,7 +3920,7 @@
 
 This code is released under the libpng license.
 
-libpng versions 1.0.7, July 1, 2000, through 1.4.21beta01, December 30, 2016, are
+libpng versions 1.0.7, July 1, 2000, through 1.4.21beta01, August 7, 2017, are
 Copyright (c) 2000-2002, 2004, 2006-2017 Glenn Randers-Pehrson, are
 derived from libpng-1.0.6, and are distributed according to the same
 disclaimer and license as libpng-1.0.6 with the following individuals
@@ -4017,7 +4017,7 @@
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-December 30, 2016
+August 7, 2017
 
 .\" end of man page
 
diff --git a/libpngpf.3 b/libpngpf.3
index 69aee01..2c182a6 100644
--- a/libpngpf.3
+++ b/libpngpf.3
@@ -1,4 +1,4 @@
-.TH LIBPNGPF 3 "December 30, 2016"
+.TH LIBPNGPF 3 "August 7, 2017"
 .SH NAME
 libpng \- Portable Network Graphics (PNG) Reference Library 1.4.21beta01
 (private functions)
diff --git a/png.5 b/png.5
index 6e786e8..b579897 100644
--- a/png.5
+++ b/png.5
@@ -1,4 +1,4 @@
-.TH PNG 5 "December 30, 2016"
+.TH PNG 5 "August 7, 2017"
 .SH NAME
 png \- Portable Network Graphics (PNG) format
 .SH DESCRIPTION
diff --git a/png.c b/png.c
index 71bc95a..78fdb29 100644
--- a/png.c
+++ b/png.c
@@ -559,14 +559,14 @@
 #else
 #ifdef __STDC__
    return ((png_charp) PNG_STRING_NEWLINE \
-     "libpng version 1.4.21beta01 - December 30, 2016" PNG_STRING_NEWLINE \
+     "libpng version 1.4.21beta01 - August 7, 2017" PNG_STRING_NEWLINE \
      "Copyright (c) 1998-2002,2004,2006-2016 Glenn Randers-Pehrson" \
      PNG_STRING_NEWLINE \
      "Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
      "Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc." \
      PNG_STRING_NEWLINE);
 #else
-   return ((png_charp) "libpng version 1.4.21beta01 - December 30, 2016\
+   return ((png_charp) "libpng version 1.4.21beta01 - August 7, 2017\
       Copyright (c) 1998-2002,2004,2006-2016 Glenn Randers-Pehrson\
       Copyright (c) 1996-1997 Andreas Dilger\
       Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.");
diff --git a/png.h b/png.h
index edb193a..b680bec 100644
--- a/png.h
+++ b/png.h
@@ -1,7 +1,7 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.4.21beta01, December 30, 2016
+ * libpng version 1.4.21beta01, August 7, 2017
  *
  * Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -12,7 +12,7 @@
  * Authors and maintainers:
  *  libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
  *  libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
- *  libpng versions 0.97, January 1998, through 1.4.21beta01, December 30, 2016: Glenn
+ *  libpng versions 0.97, January 1998, through 1.4.21beta01, August 7, 2017: Glenn
  *  See also "Contributing Authors", below.
  */
 
@@ -24,7 +24,7 @@
  *
  * This code is released under the libpng license.
  *
- * libpng versions 1.0.7, July 1, 2000, through 1.4.21beta01, December 30, 2016, are
+ * libpng versions 1.0.7, July 1, 2000, through 1.4.21beta01, August 7, 2017, are
  * Copyright (c) 2000-2002, 2004, 2006-2017 Glenn Randers-Pehrson, are
  * derived from libpng-1.0.6, and are distributed according to the same
  * disclaimer and license as libpng-1.0.6 with the following individuals
@@ -207,7 +207,7 @@
  * Y2K compliance in libpng:
  * =========================
  *
- *    December 30, 2016
+ *    August 7, 2017
  *
  *    Since the PNG Development group is an ad-hoc body, we can't make
  *    an official declaration.
@@ -271,7 +271,7 @@
 /* Version information for png.h - this should match the version in png.c */
 #define PNG_LIBPNG_VER_STRING "1.4.21beta01"
 #define PNG_HEADER_VERSION_STRING \
-   " libpng version 1.4.21beta01 - December 30, 2016\n"
+   " libpng version 1.4.21beta01 - August 7, 2017\n"
 
 #define PNG_LIBPNG_VER_SONUM   14
 #define PNG_LIBPNG_VER_DLLNUM  14
diff --git a/pngconf.h b/pngconf.h
index 8ce5dd2..7715187 100644
--- a/pngconf.h
+++ b/pngconf.h
@@ -1,7 +1,7 @@
 
 /* pngconf.h - machine configurable file for libpng
  *
- * libpng version 1.4.21beta01, December 30, 2016
+ * libpng version 1.4.21beta01, August 7, 2017
  *
  * Copyright (c) 1998-2002,2004,2006-2015 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
diff --git a/projects/vstudio/readme.txt b/projects/vstudio/readme.txt
index 612c54a..6fa0065 100644
--- a/projects/vstudio/readme.txt
+++ b/projects/vstudio/readme.txt
@@ -1,7 +1,7 @@
 
 VisualStudio instructions
 
-libpng version 1.4.21beta01 - December 30, 2016
+libpng version 1.4.21beta01 - August 7, 2017
 
 Copyright (c) 2010 Glenn Randers-Pehrson
 
diff --git a/projects/vstudio/zlib.props b/projects/vstudio/zlib.props
index 56def9d..557f439 100644
--- a/projects/vstudio/zlib.props
+++ b/projects/vstudio/zlib.props
@@ -2,7 +2,7 @@
 <!--
  * zlib.props - location of zlib source and build
  *
- * libpng version 1.4.21beta01 - December 30, 2016
+ * libpng version 1.4.21beta01 - August 7, 2017
  *
  * Copyright (c) 1998-2011 Glenn Randers-Pehrson
  *
diff --git a/scripts/README.txt b/scripts/README.txt
index 49a7cd1..5de4137 100644
--- a/scripts/README.txt
+++ b/scripts/README.txt
@@ -1,5 +1,5 @@
 
-Makefiles for  libpng version 1.4.21beta01 - December 30, 2016
+Makefiles for  libpng version 1.4.21beta01 - August 7, 2017
 
  makefile.linux    =>  Linux/ELF makefile
                        (gcc, creates libpng14.so.14.1.4.21beta01)