diff --git a/VERSION b/VERSION
index 6951ac29..5e6eb4e6 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-8.3.627
+8.3.628
diff --git a/drc/DRCbasic.c b/drc/DRCbasic.c
index ef5b7df9..cce7b8eb 100644
--- a/drc/DRCbasic.c
+++ b/drc/DRCbasic.c
@@ -796,9 +796,9 @@ drcTile (tile, dinfo, arg)
 		     * an exception area.  Exception rules are ignored if
 		     * the edge is outside an exception area.
 		     */
-		    if (!isinside && ((cptr->drcc_exception & DRC_EXCEPTION_MASK) == 0)))
+		    if (!isinside && (!(cptr->drcc_exception & DRC_EXCEPTION_MASK) == 0))
 			continue;
-		    if (isinside && ((cptr->drcc_exception & DRC_EXCEPTION_MASK) == 1)))
+		    if (isinside && ((cptr->drcc_exception & DRC_EXCEPTION_MASK) != 0))
 			continue;
 		}
 
@@ -1243,9 +1243,9 @@ drcTile (tile, dinfo, arg)
 		     * an exception area.  Exception rules are ignored if
 		     * the edge is outside an exception area.
 		     */
-		    if (!isinside && ((cptr->drcc_exception & DRC_EXCEPTION_MASK) == 0)))
+		    if (!isinside && ((cptr->drcc_exception & DRC_EXCEPTION_MASK) == 0))
 			continue;
-		    if (isinside && ((cptr->drcc_exception & DRC_EXCEPTION_MASK) == 1)))
+		    if (isinside && ((cptr->drcc_exception & DRC_EXCEPTION_MASK) != 0))
 			continue;
 		}
 
diff --git a/drc/drc.h b/drc/drc.h
index fbd1b96b..0e8a83c0 100644
--- a/drc/drc.h
+++ b/drc/drc.h
@@ -94,7 +94,7 @@ typedef struct drccookie
 
 /* drcc_exception defaults to 255 meaning no exceptions/exemptions */
 #define	DRC_EXCEPTION_NONE ((unsigned char)0xff)
-/* The high bit of the value determines if this is an exception or an exemption.
+/* The high bit of the value determines if this is an exception or an exemption. */
 #define DRC_EXCEPTION_MASK ((unsigned char)0x80)
 
 /*