diff --git a/src/rfc3987_syntax/syntax_rfc3987.lark b/src/rfc3987_syntax/syntax_rfc3987.lark
index c1973c0..365cf06 100644
--- a/src/rfc3987_syntax/syntax_rfc3987.lark
+++ b/src/rfc3987_syntax/syntax_rfc3987.lark
@@ -57,8 +57,8 @@ ifragment: (ipchar | "/" | "?")*
 
 iunreserved: alpha | digit | "-" | "." | "_" | "~" | ucschar
 
-ucschar: /[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]/
-iprivate: /[\uE000-\uF8FF]/
+ucschar: /[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF\U00010000-\U0001FFFD\U00020000-\U0002FFFD\U00030000-\U0003FFFD\U00040000-\U0004FFFD\U00050000-\U0005FFFD\U00060000-\U0006FFFD\U00070000-\U0007FFFD\U00080000-\U0008FFFD\U00090000-\U0009FFFD\U000A0000-\U000AFFFD\U000B0000-\U000BFFFD\U000C0000-\U000CFFFD\U000D0000-\U000DFFFD\U000E0000-\U000EFFFD]/
+iprivate: /[\uE000-\uF8FF\U000F0000-\U000FFFFD\U00100000-\U0010FFFD]/
 
 sub_delims: "!" | "$" | "&" | "'" | "(" | ")"
           | "*" | "+" | "," | ";" | "="
@@ -67,15 +67,15 @@ ip_literal: "[" (ipv6address | ipvfuture) "]"
 
 ipvfuture: "v" hexdig+ "." (unreserved | sub_delims | ":")+
 
-ipv6address: h16 ":" h16 ":" h16 ":" h16 ":" h16 ":" h16 ":" ls32
-           | "::" h16 ":" h16 ":" h16 ":" h16 ":" h16 ":" ls32
-           | h16 "::" h16 ":" h16 ":" h16 ":" h16 ":" ls32
-           | h16 ":" h16 "::" h16 ":" h16 ":" h16 ":" ls32
-           | h16 ":" h16 ":" h16 "::" h16 ":" h16 ":" ls32
-           | h16 ":" h16 ":" h16 ":" h16 "::" h16 ":" ls32
-           | h16 ":" h16 ":" h16 ":" h16 ":" h16 "::" ls32
-           | h16 ":" h16 ":" h16 ":" h16 ":" h16 ":" h16 "::" h16
-           | h16 ":" h16 ":" h16 ":" h16 ":" h16 ":" h16 ":" h16 "::"
+ipv6address:                                ( h16 ":" )~6 ls32
+           |                           "::" ( h16 ":" )~3 ls32
+           |                    h16?   "::" ( h16 ":" )~4 ls32
+           | ( ( h16 ":" )?     h16 )? "::" ( h16 ":" )~3 ls32
+           | ( ( h16 ":" )~0..2 h16 )? "::" ( h16 ":" )~2 ls32
+           | ( ( h16 ":" )~0..3 h16 )? "::"   h16 ":"     ls32
+           | ( ( h16 ":" )~0..4 h16 )? "::"               ls32
+           | ( ( h16 ":" )~0..5 h16 )? "::"               h16
+           | ( ( h16 ":" )~0..6 h16 )? "::"
 
 h16: hexdig
    | hexdig hexdig
diff --git a/tests/valid_syntax.json b/tests/valid_syntax.json
index 6f60090..e19b45b 100644
--- a/tests/valid_syntax.json
+++ b/tests/valid_syntax.json
@@ -108,10 +108,60 @@
             "value": "пример/тест#часть2",
             "expect_lark": true,
             "reason": ""
+        },
+        {
+            "value": "ucschar/\u00A0-\uD7FF/\uF900-\uFFCF/\uFDF0-\uFFEF",
+            "expect_lark": true,
+            "reason": "`ucschar` ranges: %xA0-D7FF / %xF900-FDCF / %xFDF0-FFEF"
+        },
+        {
+            "value": "ucschar/\uD800\uDC00-\uD83F\uDFFD/\uD840\uDC00-\uD87F\uDFFD/\uD880\uDC00-\uD8BF\uDFFD",
+            "expect_lark": true,
+            "reason": "`ucschar` ranges: %x10000-1FFFD / %x20000-2FFFD / %x30000-3FFFD"
+        },
+        {
+            "value": "ucschar/\uD8C0\uDC00-\uD8FF\uDFFD/\uD900\uDC00-\uD93F\uDFFD/\uD940\uDC00-\uD97F\uDFFD",
+            "expect_lark": true,
+            "reason": "`ucschar` ranges: %x40000-4FFFD / %x50000-5FFFD / %x60000-6FFFD"
+        },
+        {
+            "value": "ucschar/\uD980\uDC00-\uD9BF\uDFFD/\uD9C0\uDC00-\uD9FF\uDFFD/\uDA00\uDC00-\uDA3F\uDFFD",
+            "expect_lark": true,
+            "reason": "`ucschar` ranges: %x70000-7FFFD / %x80000-8FFFD / %x90000-9FFFD"
+        },
+        {
+            "value": "ucschar/\uDA40\uDC00-\uDA7F\uDFFD/\uDA80\uDC00-\uDABF\uDFFD/\uDAC0\uDC00-\uDAFF\uDFFD",
+            "expect_lark": true,
+            "reason": "`ucschar` ranges: %xA0000-AFFFD / %xB0000-BFFFD / %xC0000-CFFFD"
+        },
+        {
+            "value": "ucschar/\uDB00\uDC00-\uDB3F\uDFFD/\uDB40\uDC00-\uDB7F\uDFFD",
+            "expect_lark": true,
+            "reason": "`ucschar` ranges: %xD0000-DFFFD / %xE0000-EFFFD"
+        },
+        {
+            "value": "iprivate?foo=\uE000-\uF8FF&bar=\uDB80\uDC00-\uDBBF\uDFFD&baz=\uDBC0\uDC00-\uDBFF\uDFFD",
+            "expect_lark": true,
+            "reason": "`iprivate` ranges: %xE000-F8FF / %xF0000-FFFFD / %x100000-10FFFD"
+        },
+        {
+            "value": "//[2345:0425:2CA1:0:0:0567:5673:23b5]/foo",
+            "expect_lark": true,
+            "reason": "`IPv6address` case: 6( h16 \":\" ) ls32"
+        },
+        {
+            "value": "//[2345::BEEF]/foo",
+            "expect_lark": true,
+            "reason": "`IPv6address` case: [ *5( h16 \":\" ) h16 ] \"::\" h16"
+        },
+        {
+            "value": "//[2041:0:140F::875B:131B]/foo",
+            "expect_lark": true,
+            "reason": "`IPv6address` case: [ *4( h16 \":\" ) h16 ] \"::\" ls32"
         }
     ],
     "reserved": [],
     "scheme": [],
     "pct_encoded": [],
     "ipv4address": []
-}
\ No newline at end of file
+}