diff --git a/util/opt/alloc.c b/util/opt/alloc.c
index bcb86d0b..5d095643 100644
--- a/util/opt/alloc.c
+++ b/util/opt/alloc.c
@@ -12,19 +12,8 @@ static char rcsid[] = "$Header$";
 #include "proinf.h"
 
 /*
- * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
- *
- *          This product is part of the Amsterdam Compiler Kit.
- *
- * Permission to use, sell, duplicate or disclose this software must be
- * obtained in writing. Requests for such permissions may be sent to
- *
- *      Dr. Andrew S. Tanenbaum
- *      Wiskundig Seminarium
- *      Vrije Universiteit
- *      Postbox 7161
- *      1007 MC Amsterdam
- *      The Netherlands
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
  *
  * Author: Hans van Staveren
  */
diff --git a/util/opt/backward.c b/util/opt/backward.c
index eca9f9ec..907d27e2 100644
--- a/util/opt/backward.c
+++ b/util/opt/backward.c
@@ -15,19 +15,8 @@ static char rcsid[] = "$Header$";
 #include "ext.h"
 
 /*
- * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
- *
- *          This product is part of the Amsterdam Compiler Kit.
- *
- * Permission to use, sell, duplicate or disclose this software must be
- * obtained in writing. Requests for such permissions may be sent to
- *
- *      Dr. Andrew S. Tanenbaum
- *      Wiskundig Seminarium
- *      Vrije Universiteit
- *      Postbox 7161
- *      1007 MC Amsterdam
- *      The Netherlands
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
  *
  * Author: Hans van Staveren
  */
diff --git a/util/opt/cleanup.c b/util/opt/cleanup.c
index d4525d4a..aa5db030 100644
--- a/util/opt/cleanup.c
+++ b/util/opt/cleanup.c
@@ -13,19 +13,8 @@ static char rcsid[] = "$Header$";
 #include "ext.h"
 
 /*
- * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
- *
- *          This product is part of the Amsterdam Compiler Kit.
- *
- * Permission to use, sell, duplicate or disclose this software must be
- * obtained in writing. Requests for such permissions may be sent to
- *
- *      Dr. Andrew S. Tanenbaum
- *      Wiskundig Seminarium
- *      Vrije Universiteit
- *      Postbox 7161
- *      1007 MC Amsterdam
- *      The Netherlands
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
  *
  * Author: Hans van Staveren
  */
diff --git a/util/opt/flow.c b/util/opt/flow.c
index b83c39bd..a315e42a 100644
--- a/util/opt/flow.c
+++ b/util/opt/flow.c
@@ -14,19 +14,8 @@ static char rcsid[] = "$Header$";
 #include "ext.h"
 
 /*
- * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
- *
- *          This product is part of the Amsterdam Compiler Kit.
- *
- * Permission to use, sell, duplicate or disclose this software must be
- * obtained in writing. Requests for such permissions may be sent to
- *
- *      Dr. Andrew S. Tanenbaum
- *      Wiskundig Seminarium
- *      Vrije Universiteit
- *      Postbox 7161
- *      1007 MC Amsterdam
- *      The Netherlands
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
  *
  * Author: Hans van Staveren
  */
diff --git a/util/opt/getline.c b/util/opt/getline.c
index e85bfd33..8a5fd8c8 100644
--- a/util/opt/getline.c
+++ b/util/opt/getline.c
@@ -16,19 +16,8 @@ static char rcsid[] = "$Header$";
 #include "ext.h"
 
 /*
- * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
- *
- *          This product is part of the Amsterdam Compiler Kit.
- *
- * Permission to use, sell, duplicate or disclose this software must be
- * obtained in writing. Requests for such permissions may be sent to
- *
- *      Dr. Andrew S. Tanenbaum
- *      Wiskundig Seminarium
- *      Vrije Universiteit
- *      Postbox 7161
- *      1007 MC Amsterdam
- *      The Netherlands
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
  *
  * Author: Hans van Staveren
  */
diff --git a/util/opt/lookup.c b/util/opt/lookup.c
index d6126e34..3eb51b04 100644
--- a/util/opt/lookup.c
+++ b/util/opt/lookup.c
@@ -9,19 +9,8 @@ static char rcsid[] = "$Header$";
 #include "proinf.h"
 
 /*
- * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
- *
- *          This product is part of the Amsterdam Compiler Kit.
- *
- * Permission to use, sell, duplicate or disclose this software must be
- * obtained in writing. Requests for such permissions may be sent to
- *
- *      Dr. Andrew S. Tanenbaum
- *      Wiskundig Seminarium
- *      Vrije Universiteit
- *      Postbox 7161
- *      1007 MC Amsterdam
- *      The Netherlands
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
  *
  * Author: Hans van Staveren
  */
diff --git a/util/opt/main.c b/util/opt/main.c
index 11b274fd..853e3e57 100644
--- a/util/opt/main.c
+++ b/util/opt/main.c
@@ -10,19 +10,8 @@ static char rcsid[] = "$Header$";
 #include "ext.h"
 
 /*
- * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
- *
- *          This product is part of the Amsterdam Compiler Kit.
- *
- * Permission to use, sell, duplicate or disclose this software must be
- * obtained in writing. Requests for such permissions may be sent to
- *
- *      Dr. Andrew S. Tanenbaum
- *      Wiskundig Seminarium
- *      Vrije Universiteit
- *      Postbox 7161
- *      1007 MC Amsterdam
- *      The Netherlands
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
  *
  * Author: Hans van Staveren
  */
diff --git a/util/opt/mktab.y b/util/opt/mktab.y
index 969c068a..b88f4e2a 100644
--- a/util/opt/mktab.y
+++ b/util/opt/mktab.y
@@ -12,19 +12,8 @@ static char rcsid[] = "$Header$";
 #include "optim.h"
 
 /*
- * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
- *
- *          This product is part of the Amsterdam Compiler Kit.
- *
- * Permission to use, sell, duplicate or disclose this software must be
- * obtained in writing. Requests for such permissions may be sent to
- *
- *      Dr. Andrew S. Tanenbaum
- *      Wiskundig Seminarium
- *      Vrije Universiteit
- *      Postbox 7161
- *      1007 MC Amsterdam
- *      The Netherlands
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
  *
  * Author: Hans van Staveren
  */
diff --git a/util/opt/peephole.c b/util/opt/peephole.c
index 3b013cb4..fdbc8af3 100644
--- a/util/opt/peephole.c
+++ b/util/opt/peephole.c
@@ -16,19 +16,8 @@ static char rcsid[] = "$Header$";
 #include "ext.h"
 
 /*
- * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
- *
- *          This product is part of the Amsterdam Compiler Kit.
- *
- * Permission to use, sell, duplicate or disclose this software must be
- * obtained in writing. Requests for such permissions may be sent to
- *
- *      Dr. Andrew S. Tanenbaum
- *      Wiskundig Seminarium
- *      Vrije Universiteit
- *      Postbox 7161
- *      1007 MC Amsterdam
- *      The Netherlands
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
  *
  * Author: Hans van Staveren
  */
diff --git a/util/opt/process.c b/util/opt/process.c
index d6c60683..357a8fed 100644
--- a/util/opt/process.c
+++ b/util/opt/process.c
@@ -14,19 +14,8 @@ static char rcsid[] = "$Header$";
 #include "ext.h"
 
 /*
- * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
- *
- *          This product is part of the Amsterdam Compiler Kit.
- *
- * Permission to use, sell, duplicate or disclose this software must be
- * obtained in writing. Requests for such permissions may be sent to
- *
- *      Dr. Andrew S. Tanenbaum
- *      Wiskundig Seminarium
- *      Vrije Universiteit
- *      Postbox 7161
- *      1007 MC Amsterdam
- *      The Netherlands
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
  *
  * Author: Hans van Staveren
  */
diff --git a/util/opt/putline.c b/util/opt/putline.c
index afa49f76..2c2ab86d 100644
--- a/util/opt/putline.c
+++ b/util/opt/putline.c
@@ -17,19 +17,8 @@ static char rcsid[] = "$Header$";
 #include "ext.h"
 
 /*
- * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
- *
- *          This product is part of the Amsterdam Compiler Kit.
- *
- * Permission to use, sell, duplicate or disclose this software must be
- * obtained in writing. Requests for such permissions may be sent to
- *
- *      Dr. Andrew S. Tanenbaum
- *      Wiskundig Seminarium
- *      Vrije Universiteit
- *      Postbox 7161
- *      1007 MC Amsterdam
- *      The Netherlands
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
  *
  * Author: Hans van Staveren
  */
diff --git a/util/opt/reg.c b/util/opt/reg.c
index 9c1081c6..c3da3552 100644
--- a/util/opt/reg.c
+++ b/util/opt/reg.c
@@ -14,19 +14,8 @@ static char rcsid[] = "$Header$";
 #include "ext.h"
 
 /*
- * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
- *
- *          This product is part of the Amsterdam Compiler Kit.
- *
- * Permission to use, sell, duplicate or disclose this software must be
- * obtained in writing. Requests for such permissions may be sent to
- *
- *      Dr. Andrew S. Tanenbaum
- *      Wiskundig Seminarium
- *      Vrije Universiteit
- *      Postbox 7161
- *      1007 MC Amsterdam
- *      The Netherlands
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
  *
  * Author: Hans van Staveren
  */
diff --git a/util/opt/scan.l b/util/opt/scan.l
index 660c97a7..c51445c1 100644
--- a/util/opt/scan.l
+++ b/util/opt/scan.l
@@ -4,19 +4,8 @@ static char rcsid2[] = "$Header$";
 #endif
 
 /*
- * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
- *
- *          This product is part of the Amsterdam Compiler Kit.
- *
- * Permission to use, sell, duplicate or disclose this software must be
- * obtained in writing. Requests for such permissions may be sent to
- *
- *      Dr. Andrew S. Tanenbaum
- *      Wiskundig Seminarium
- *      Vrije Universiteit
- *      Postbox 7161
- *      1007 MC Amsterdam
- *      The Netherlands
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
  *
  * Author: Hans van Staveren
  */
diff --git a/util/opt/special.c b/util/opt/special.c
index 5147aa90..08f124fd 100644
--- a/util/opt/special.c
+++ b/util/opt/special.c
@@ -6,19 +6,8 @@ static char rcsid[] = "$Header$";
 #include "types.h"
 
 /*
- * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
- *
- *          This product is part of the Amsterdam Compiler Kit.
- *
- * Permission to use, sell, duplicate or disclose this software must be
- * obtained in writing. Requests for such permissions may be sent to
- *
- *      Dr. Andrew S. Tanenbaum
- *      Wiskundig Seminarium
- *      Vrije Universiteit
- *      Postbox 7161
- *      1007 MC Amsterdam
- *      The Netherlands
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
  *
  * Author: Hans van Staveren
  */
diff --git a/util/opt/util.c b/util/opt/util.c
index 85529cdc..a6835cbd 100644
--- a/util/opt/util.c
+++ b/util/opt/util.c
@@ -12,19 +12,8 @@ static char rcsid[] = "$Header$";
 #include "ext.h"
 
 /*
- * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
- *
- *          This product is part of the Amsterdam Compiler Kit.
- *
- * Permission to use, sell, duplicate or disclose this software must be
- * obtained in writing. Requests for such permissions may be sent to
- *
- *      Dr. Andrew S. Tanenbaum
- *      Wiskundig Seminarium
- *      Vrije Universiteit
- *      Postbox 7161
- *      1007 MC Amsterdam
- *      The Netherlands
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
  *
  * Author: Hans van Staveren
  */
diff --git a/util/opt/var.c b/util/opt/var.c
index 9d5be0a5..3eea009c 100644
--- a/util/opt/var.c
+++ b/util/opt/var.c
@@ -9,19 +9,8 @@ static char rcsid[] = "$Header$";
 #include "proinf.h"
 
 /*
- * (c) copyright 1983 by the Vrije Universiteit, Amsterdam, The Netherlands.
- *
- *          This product is part of the Amsterdam Compiler Kit.
- *
- * Permission to use, sell, duplicate or disclose this software must be
- * obtained in writing. Requests for such permissions may be sent to
- *
- *      Dr. Andrew S. Tanenbaum
- *      Wiskundig Seminarium
- *      Vrije Universiteit
- *      Postbox 7161
- *      1007 MC Amsterdam
- *      The Netherlands
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
  *
  * Author: Hans van Staveren
  */