diff --git a/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/VersionUtilities.java b/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/VersionUtilities.java
index 7091cdf162..6a2d3c504a 100644
--- a/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/VersionUtilities.java
+++ b/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/VersionUtilities.java
@@ -328,7 +328,7 @@ public static boolean isSemVer(String version) {
     if (Utilities.noString(version)) {
       return false;
     }
-    return version.matches("^(0|[1-9]\\d*)\\.(0|[1-9]\\d*)\\.(0|[1-9]\\d*)(?:-((?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-\\+]*)(?:\\.(?:0|[1-9]\\d*|\\d*[a-zA-Z-\\+][0-9a-zA-Z-\\+]*))*))?$");
+    return version.matches("^(0|[1-9]\\d*)\\.(0|[1-9]\\d*)\\.(0|[1-9]\\d*)(?:-((?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\\.(?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\\+([0-9a-zA-Z-]+(?:\\.[0-9a-zA-Z-]+)*))?$");
   }
 
   /** 
diff --git a/org.hl7.fhir.utilities/src/test/java/org/hl7/fhir/utilities/VersionUtilitiesTest.java b/org.hl7.fhir.utilities/src/test/java/org/hl7/fhir/utilities/VersionUtilitiesTest.java
index ff2898b042..8a32c22765 100644
--- a/org.hl7.fhir.utilities/src/test/java/org/hl7/fhir/utilities/VersionUtilitiesTest.java
+++ b/org.hl7.fhir.utilities/src/test/java/org/hl7/fhir/utilities/VersionUtilitiesTest.java
@@ -12,6 +12,7 @@ public void isValidSemVer() {
     assertTrue(VersionUtilities.isSemVer("0.1.1"));
     assertTrue(VersionUtilities.isSemVer("0.1.1-ballot1"));
     assertTrue(VersionUtilities.isSemVer("0.0.0-alpha.0.131"));
+    assertTrue(VersionUtilities.isSemVer("1.0.0+20130313144700"));
     assertFalse(VersionUtilities.isSemVer("0.1.a"));
   }