diff --git a/icu4c/data/en_US_POSIX.txt b/icu4c/data/en_US_POSIX.txt
index 0ae240b487a..3dc884bc6c0 100644
--- a/icu4c/data/en_US_POSIX.txt
+++ b/icu4c/data/en_US_POSIX.txt
@@ -3,28 +3,26 @@
 // *   Copyright (C) 1997-2001, International Business Machines
 // *   Corporation and others.  All Rights Reserved.
 // *
-// *   Dates are RFC 1123 (LONG,LONG), RFC 850 (MED,MED), ANSI C (SHORT,SHORT) 
-// *   Use (FULL,FULL) for sortable strings.  Must use GMT time zone.
-// *
 // *******************************************************************************
 
 en_US_POSIX {
     CollationElements { 
-	    Version { "1.0" }
-		Override { "FALSE" }
-		Sequence { "& '\u0040' < A < B < C < D < E < F < G < H < I < J < K < L < M"
+        Version { "1.0" }
+        Override { "FALSE" }
+        Sequence { "& '\u0040' < A < B < C < D < E < F < G < H < I < J < K < L < M"
         " < N < O < P < Q < R < S < T < U < V < W < X < Y < Z"
         " & '\u0060' < a < b < c < d < e < f < g < h < i < j < k < l < m"
         " < n < o < p < q < r < s < t < u < v < w < x < y < z"
         " & '\u00BF' < \u00C0 < \u00C1 < \u00C2 < \u00C3 < \u00C4 < \u00C5 < \u00C6"
-	" < \u00C7 < \u00C8 < \u00C9 < \u00CA < \u00CB < \u00CC < \u00CD < \u00CE < \u00CF"
+        " < \u00C7 < \u00C8 < \u00C9 < \u00CA < \u00CB < \u00CC < \u00CD < \u00CE < \u00CF"
         " < \u00D0 < \u00D1 < \u00D2 < \u00D3 < \u00D4 < \u00D5 < \u00D6 < \u00D7"
-	" < \u00D8 < \u00D9 < \u00DA < \u00DB < \u00DC < \u00DD < \u00DE < \u00DF"
+        " < \u00D8 < \u00D9 < \u00DA < \u00DB < \u00DC < \u00DD < \u00DE < \u00DF"
         " < \u00E0 < \u00E1 < \u00E2 < \u00E3 < \u00E4 < \u00E5 < \u00E6 < \u00E7"
-	" < \u00E8 < \u00E9 < \u00EA < \u00EB < \u00EC < \u00ED < \u00EE < \u00EF"
+        " < \u00E8 < \u00E9 < \u00EA < \u00EB < \u00EC < \u00ED < \u00EE < \u00EF"
         " < \u00F0 < \u00F1 < \u00F2 < \u00F3 < \u00F4 < \u00F5 < \u00F6 < \u00F7"
-	" < \u00F8 < \u00F9 < \u00FA < \u00FB < \u00FC < \u00FD < \u00FE < \u00FF" }
+        " < \u00F8 < \u00F9 < \u00FA < \u00FB < \u00FC < \u00FD < \u00FE < \u00FF" }
     }
+    // No grouping separators
     NumberPatterns { 
             "###0.###;-###0.###",
             "\u00A4 ###0.00;-\u00A4 ###0.00",
@@ -40,28 +38,8 @@ en_US_POSIX {
             "-",
             "E",
             "0/00",
-            "INF",
+            "INF",  // Older programs can parse infinity this way.
             "\uFFFD",
     }
-    DateTimePatterns { 
-            "HH:mm:ss",
-            "HH:mm:ss z",
-            "HH:mm:ss z",
-            "HH:mm:ss yyyy",
-            "yyyy-MM-dd",
-            "EEE, dd MMM yyyy",
-            "EEEE, dd-MMM-yy",
-            "EEE MMM d",
-            "{1} {0}",
-    }
     LocaleString { "en_US_POSIX" }
-    zoneStrings { 
-        {
-                "Africa/Casablanca",
-                "GMT",
-                "GMT",
-                "GMT",
-                "GMT",
-        }
-    }
 }
diff --git a/icu4c/source/data/locales/en_US_POSIX.txt b/icu4c/source/data/locales/en_US_POSIX.txt
index 0ae240b487a..3dc884bc6c0 100644
--- a/icu4c/source/data/locales/en_US_POSIX.txt
+++ b/icu4c/source/data/locales/en_US_POSIX.txt
@@ -3,28 +3,26 @@
 // *   Copyright (C) 1997-2001, International Business Machines
 // *   Corporation and others.  All Rights Reserved.
 // *
-// *   Dates are RFC 1123 (LONG,LONG), RFC 850 (MED,MED), ANSI C (SHORT,SHORT) 
-// *   Use (FULL,FULL) for sortable strings.  Must use GMT time zone.
-// *
 // *******************************************************************************
 
 en_US_POSIX {
     CollationElements { 
-	    Version { "1.0" }
-		Override { "FALSE" }
-		Sequence { "& '\u0040' < A < B < C < D < E < F < G < H < I < J < K < L < M"
+        Version { "1.0" }
+        Override { "FALSE" }
+        Sequence { "& '\u0040' < A < B < C < D < E < F < G < H < I < J < K < L < M"
         " < N < O < P < Q < R < S < T < U < V < W < X < Y < Z"
         " & '\u0060' < a < b < c < d < e < f < g < h < i < j < k < l < m"
         " < n < o < p < q < r < s < t < u < v < w < x < y < z"
         " & '\u00BF' < \u00C0 < \u00C1 < \u00C2 < \u00C3 < \u00C4 < \u00C5 < \u00C6"
-	" < \u00C7 < \u00C8 < \u00C9 < \u00CA < \u00CB < \u00CC < \u00CD < \u00CE < \u00CF"
+        " < \u00C7 < \u00C8 < \u00C9 < \u00CA < \u00CB < \u00CC < \u00CD < \u00CE < \u00CF"
         " < \u00D0 < \u00D1 < \u00D2 < \u00D3 < \u00D4 < \u00D5 < \u00D6 < \u00D7"
-	" < \u00D8 < \u00D9 < \u00DA < \u00DB < \u00DC < \u00DD < \u00DE < \u00DF"
+        " < \u00D8 < \u00D9 < \u00DA < \u00DB < \u00DC < \u00DD < \u00DE < \u00DF"
         " < \u00E0 < \u00E1 < \u00E2 < \u00E3 < \u00E4 < \u00E5 < \u00E6 < \u00E7"
-	" < \u00E8 < \u00E9 < \u00EA < \u00EB < \u00EC < \u00ED < \u00EE < \u00EF"
+        " < \u00E8 < \u00E9 < \u00EA < \u00EB < \u00EC < \u00ED < \u00EE < \u00EF"
         " < \u00F0 < \u00F1 < \u00F2 < \u00F3 < \u00F4 < \u00F5 < \u00F6 < \u00F7"
-	" < \u00F8 < \u00F9 < \u00FA < \u00FB < \u00FC < \u00FD < \u00FE < \u00FF" }
+        " < \u00F8 < \u00F9 < \u00FA < \u00FB < \u00FC < \u00FD < \u00FE < \u00FF" }
     }
+    // No grouping separators
     NumberPatterns { 
             "###0.###;-###0.###",
             "\u00A4 ###0.00;-\u00A4 ###0.00",
@@ -40,28 +38,8 @@ en_US_POSIX {
             "-",
             "E",
             "0/00",
-            "INF",
+            "INF",  // Older programs can parse infinity this way.
             "\uFFFD",
     }
-    DateTimePatterns { 
-            "HH:mm:ss",
-            "HH:mm:ss z",
-            "HH:mm:ss z",
-            "HH:mm:ss yyyy",
-            "yyyy-MM-dd",
-            "EEE, dd MMM yyyy",
-            "EEEE, dd-MMM-yy",
-            "EEE MMM d",
-            "{1} {0}",
-    }
     LocaleString { "en_US_POSIX" }
-    zoneStrings { 
-        {
-                "Africa/Casablanca",
-                "GMT",
-                "GMT",
-                "GMT",
-                "GMT",
-        }
-    }
 }