diff --git a/pygments/lexers/int_fiction.py b/pygments/lexers/int_fiction.py
index 0e7c81802c..a31a1e31c0 100644
--- a/pygments/lexers/int_fiction.py
+++ b/pygments/lexers/int_fiction.py
@@ -125,7 +125,7 @@ class Inform6Lexer(RegexLexer):
             (r'[%s]' % _squote, String.Single, ('#pop', 'dictionary-word')),
             (r'[%s]' % _dquote, String.Double, ('#pop', 'string')),
             # Numbers
-            (r'\$[+%s][0-9]*\.?[0-9]*([eE][+%s]?[0-9]+)?' % (_dash, _dash),
+            (r'\$[<>]?[+%s][0-9]*\.?[0-9]*([eE][+%s]?[0-9]+)?' % (_dash, _dash),
              Number.Float, '#pop'),
             (r'\$[0-9a-fA-F]+', Number.Hex, '#pop'),
             (r'\$\$[01]+', Number.Bin, '#pop'),
@@ -160,9 +160,10 @@ class Inform6Lexer(RegexLexer):
             # Other built-in symbols
             (words((
                 'call', 'copy', 'create', 'DEBUG', 'destroy', 'DICT_CHAR_SIZE',
-                'DICT_ENTRY_BYTES', 'DICT_IS_UNICODE', 'DICT_WORD_SIZE', 'false',
-                'FLOAT_INFINITY', 'FLOAT_NAN', 'FLOAT_NINFINITY', 'GOBJFIELD_CHAIN',
-                'GOBJFIELD_CHILD', 'GOBJFIELD_NAME', 'GOBJFIELD_PARENT',
+                'DICT_ENTRY_BYTES', 'DICT_IS_UNICODE', 'DICT_WORD_SIZE', 'DOUBLE_HI_INFINITY',
+                'DOUBLE_HI_NAN', 'DOUBLE_HI_NINFINITY', 'DOUBLE_LO_INFINITY', 'DOUBLE_LO_NAN',
+                'DOUBLE_LO_NINFINITY', 'false', 'FLOAT_INFINITY', 'FLOAT_NAN', 'FLOAT_NINFINITY',
+                'GOBJFIELD_CHAIN', 'GOBJFIELD_CHILD', 'GOBJFIELD_NAME', 'GOBJFIELD_PARENT',
                 'GOBJFIELD_PROPTAB', 'GOBJFIELD_SIBLING', 'GOBJ_EXT_START',
                 'GOBJ_TOTAL_LENGTH', 'Grammar__Version', 'INDIV_PROP_START', 'INFIX',
                 'infix__watching', 'MODULE_MODE', 'name', 'nothing', 'NUM_ATTR_BYTES', 'print',
@@ -411,7 +412,8 @@ class Inform6Lexer(RegexLexer):
         ],
         'property-keyword*': [
             include('_whitespace'),
-            (words(('additive', 'individual', 'long'), suffix=r'\b(?!(\s*|(![^%s]*))*;)' % _newline),
+            (words(('additive', 'individual', 'long'),
+                suffix=r'\b(?=(\s*|(![^%s]*[%s]))*[_a-zA-Z])' % (_newline, _newline)),
              Keyword),
             default('#pop')
         ],
diff --git a/tests/examplefiles/inform6/inform6_example b/tests/examplefiles/inform6/inform6_example
index 3eaef8c75e..c7d5de6745 100644
--- a/tests/examplefiles/inform6/inform6_example
+++ b/tests/examplefiles/inform6/inform6_example
@@ -73,7 +73,7 @@ Property long
     ! to the semicolon
     ;
 Property additive;
-Property individual;
+Property individual 1;
 Iffalse true;
 Property long individual;
 Property long individual individual;
@@ -334,6 +334,8 @@ Extend only 'feel' 'touch' replace * noun -> Feel;
         a = '''; ! character
         a = $09afAF;
         a = $$01;
+        a = $+1.0;
+        a = $<-1E-3;
         a = ##Eat; a = #a$Eat;
         a = #g$self;
         a = #n$!word;
diff --git a/tests/examplefiles/inform6/inform6_example.output b/tests/examplefiles/inform6/inform6_example.output
index 404cb052c2..ccff13bebc 100644
--- a/tests/examplefiles/inform6/inform6_example.output
+++ b/tests/examplefiles/inform6/inform6_example.output
@@ -525,6 +525,9 @@
 'Property'    Keyword
 ' '           Text
 'individual'  Name.Constant
+' '           Text
+''            Text
+'1'           Literal.Number.Integer
 ''            Punctuation
 ';'           Punctuation
 '\n'          Text
@@ -3478,6 +3481,26 @@
 '='           Operator
 ' '           Text
 ''            Text
+'$+1.0'       Literal.Number.Float
+''            Punctuation
+';'           Punctuation
+'\n        '  Text
+''            Text
+'a'           Name
+' '           Text
+'='           Operator
+' '           Text
+''            Text
+'$<-1E-3'     Literal.Number.Float
+''            Punctuation
+';'           Punctuation
+'\n        '  Text
+''            Text
+'a'           Name
+' '           Text
+'='           Operator
+' '           Text
+''            Text
 '##'          Operator
 'Eat'         Name
 ''            Punctuation