diff --git a/apns2/errors.py b/apns2/errors.py
index 1a71a9c..03642b2 100644
--- a/apns2/errors.py
+++ b/apns2/errors.py
@@ -2,6 +2,10 @@ class APNsException(Exception):
     pass
 
 
+class ConnectionFailed(APNsException):
+    """There was an error connecting to APNs."""
+
+
 class InternalException(APNsException):
     """This exception should not be raised. If it is, please report this as a bug."""
     pass
@@ -12,44 +16,8 @@ class BadPayloadException(APNsException):
     pass
 
 
-class PayloadEmpty(BadPayloadException):
-    """The message payload was empty."""
-    pass
-
-
-class PayloadTooLarge(BadPayloadException):
-    """The message payload was too large. The maximum payload size is 4096 bytes."""
-    pass
-
-
-class BadTopic(BadPayloadException):
-    """The apns-topic was invalid."""
-    pass
-
-
-class TopicDisallowed(BadPayloadException):
-    """Pushing to this topic is not allowed."""
-    pass
-
-
-class BadMessageId(InternalException):
-    """The apns-id value is bad."""
-    pass
-
-
-class BadExpirationDate(BadPayloadException):
-    """The apns-expiration value is bad."""
-    pass
-
-
-class BadPriority(InternalException):
-    """The apns-priority value is bad."""
-    pass
-
-
-class MissingDeviceToken(APNsException):
-    """The device token is not specified in the request :path.
-    Verify that the :path header contains the device token."""
+class BadCollapseId(BadPayloadException):
+    """The collapse identifier exceeds the maximum allowed size"""
     pass
 
 
@@ -59,21 +27,60 @@ class BadDeviceToken(APNsException):
     pass
 
 
+class BadExpirationDate(BadPayloadException):
+    """The apns-expiration value is bad."""
+    pass
+
+
+class BadMessageId(InternalException):
+    """The apns-id value is bad."""
+    pass
+
+
+class BadPriority(InternalException):
+    """The apns-priority value is bad."""
+    pass
+
+
+class BadTopic(BadPayloadException):
+    """The apns-topic was invalid."""
+    pass
+
+
 class DeviceTokenNotForTopic(APNsException):
     """The device token does not match the specified topic."""
 
 
-class Unregistered(APNsException):
-    """The device token is inactive for the specified topic."""
-
-
 class DuplicateHeaders(InternalException):
     """One or more headers were repeated."""
     pass
 
 
-class BadCertificateEnvironment(APNsException):
-    """The client certificate was for the wrong environment."""
+class IdleTimeout(APNsException):
+    """Idle time out."""
+    pass
+
+
+class MissingDeviceToken(APNsException):
+    """The device token is not specified in the request :path.
+    Verify that the :path header contains the device token."""
+    pass
+
+
+class MissingTopic(BadPayloadException):
+    """The apns-topic header of the request was not specified and was required.
+    The apns-topic header is mandatory when the client is connected using a certificate
+    that supports multiple topics."""
+    pass
+
+
+class PayloadEmpty(BadPayloadException):
+    """The message payload was empty."""
+    pass
+
+
+class TopicDisallowed(BadPayloadException):
+    """Pushing to this topic is not allowed."""
     pass
 
 
@@ -82,11 +89,32 @@ class BadCertificate(APNsException):
     pass
 
 
+class BadCertificateEnvironment(APNsException):
+    """The client certificate was for the wrong environment."""
+    pass
+
+
+class ExpiredProviderToken(APNsException):
+    """The provider token is stale and a new token should be generated."""
+    pass
+
+
 class Forbidden(APNsException):
     """The specified action is not allowed."""
     pass
 
 
+class InvalidProviderToken(APNsException):
+    """The provider token is not valid or the token signature could not be verified."""
+    pass
+
+
+class MissingProviderToken(APNsException):
+    """No provider certificate was used to connect to APNs and Authorization header was missing or no provider token 
+    was specified. """
+    pass
+
+
 class BadPath(APNsException):
     """The request contained a bad :path value."""
     pass
@@ -97,21 +125,25 @@ class MethodNotAllowed(InternalException):
     pass
 
 
+class Unregistered(APNsException):
+    """The device token is inactive for the specified topic."""
+
+
+class PayloadTooLarge(BadPayloadException):
+    """The message payload was too large. The maximum payload size is 4096 bytes."""
+    pass
+
+
+class TooManyProviderTokenUpdates(APNsException):
+    """The provider token is being updated too often."""
+    pass
+
+
 class TooManyRequests(APNsException):
     """Too many requests were made consecutively to the same device token."""
     pass
 
 
-class IdleTimeout(APNsException):
-    """Idle time out."""
-    pass
-
-
-class Shutdown(APNsException):
-    """The server is shutting down."""
-    pass
-
-
 class InternalServerError(APNsException):
     """An internal server error occurred."""
     pass
@@ -122,40 +154,39 @@ class ServiceUnavailable(APNsException):
     pass
 
 
-class MissingTopic(BadPayloadException):
-    """The apns-topic header of the request was not specified and was required.
-    The apns-topic header is mandatory when the client is connected using a certificate
-    that supports multiple topics."""
+class Shutdown(APNsException):
+    """The server is shutting down."""
     pass
 
 
-class ConnectionFailed(APNsException):
-    """There was an error connecting to APNs."""
-
-
 def exception_class_for_reason(reason):
     return {
-        'PayloadEmpty': PayloadEmpty,
-        'PayloadTooLarge': PayloadTooLarge,
-        'BadTopic': BadTopic,
-        'TopicDisallowed': TopicDisallowed,
-        'BadMessageId': BadMessageId,
-        'BadExpirationDate': BadExpirationDate,
-        'BadPriority': BadPriority,
-        'MissingDeviceToken': MissingDeviceToken,
+        'BadCollapseId': BadCollapseId,
         'BadDeviceToken': BadDeviceToken,
+        'BadExpirationDate': BadExpirationDate,
+        'BadMessageId': BadMessageId,
+        'BadPriority': BadPriority,
+        'BadTopic': BadTopic,
         'DeviceTokenNotForTopic': DeviceTokenNotForTopic,
-        'Unregistered': Unregistered,
         'DuplicateHeaders': DuplicateHeaders,
-        'BadCertificateEnvironment': BadCertificateEnvironment,
+        'IdleTimeout': IdleTimeout,
+        'MissingDeviceToken': MissingDeviceToken,
+        'MissingTopic': MissingTopic,
+        'PayloadEmpty': PayloadEmpty,
+        'TopicDisallowed': TopicDisallowed,
         'BadCertificate': BadCertificate,
+        'BadCertificateEnvironment': BadCertificateEnvironment,
+        'ExpiredProviderToken': ExpiredProviderToken,
         'Forbidden': Forbidden,
+        'InvalidProviderToken': InvalidProviderToken,
+        'MissingProviderToken': MissingProviderToken,
         'BadPath': BadPath,
         'MethodNotAllowed': MethodNotAllowed,
+        'Unregistered': Unregistered,
+        'PayloadTooLarge': PayloadTooLarge,
+        'TooManyProviderTokenUpdates': TooManyProviderTokenUpdates,
         'TooManyRequests': TooManyRequests,
-        'IdleTimeout': IdleTimeout,
-        'Shutdown': Shutdown,
         'InternalServerError': InternalServerError,
         'ServiceUnavailable': ServiceUnavailable,
-        'MissingTopic': MissingTopic,
+        'Shutdown': Shutdown,
     }[reason]