diff --git a/neo/io/axographio.py b/neo/io/axographio.py
index 1c79117e6..822582a1a 100644
--- a/neo/io/axographio.py
+++ b/neo/io/axographio.py
@@ -49,7 +49,6 @@ class AxographIO(AxographRawIO, BaseFromRaw):
     description = 'This IO reads .axgd/.axgx files created with AxoGraph'
 
     _prefered_signal_group_mode = 'group-by-same-units'
-    _default_group_mode_have_change_in_0_9 = True
 
     def __init__(self, filename='', force_single_segment=False):
         AxographRawIO.__init__(self, filename, force_single_segment)
diff --git a/neo/io/axonio.py b/neo/io/axonio.py
index b82404835..02a83b2a2 100644
--- a/neo/io/axonio.py
+++ b/neo/io/axonio.py
@@ -37,7 +37,6 @@ class AxonIO(AxonRawIO, BaseFromRaw):
 
     """
     _prefered_signal_group_mode = 'group-by-same-units'
-    _default_group_mode_have_change_in_0_9 = True
 
     def __init__(self, filename):
         AxonRawIO.__init__(self, filename=filename)
diff --git a/neo/io/basefromrawio.py b/neo/io/basefromrawio.py
index 6572cfef9..788f6cb8a 100644
--- a/neo/io/basefromrawio.py
+++ b/neo/io/basefromrawio.py
@@ -68,7 +68,6 @@ class BaseFromRaw(BaseIO):
     mode = 'file'
 
     _prefered_signal_group_mode = 'group-by-same-units'  # 'split-all'
-    _default_group_mode_have_change_in_0_9 = False
 
     def __init__(self, *args, **kargs):
         BaseIO.__init__(self, *args, **kargs)
@@ -103,9 +102,6 @@ def read_block(self, block_index=0, lazy=False,
 
         if signal_group_mode is None:
             signal_group_mode = self._prefered_signal_group_mode
-            if self._default_group_mode_have_change_in_0_9:
-                warnings.warn('default "signal_group_mode" have change in version 0.9:'
-                        'now all channels are group together in AnalogSignal')
 
         l = ['AnalogSignal', 'SpikeTrain', 'Event', 'Epoch']
         if create_group_across_segment is None:
diff --git a/neo/io/bci2000io.py b/neo/io/bci2000io.py
index 55daacf7d..1318c46be 100644
--- a/neo/io/bci2000io.py
+++ b/neo/io/bci2000io.py
@@ -5,7 +5,6 @@
 class BCI2000IO(BCI2000RawIO, BaseFromRaw):
     """Class for reading data from a BCI2000 .dat file, either version 1.0 or 1.1"""
     _prefered_signal_group_mode = 'group-by-same-units'
-    _default_group_mode_have_change_in_0_9 = True
 
     def __init__(self, filename):
         BCI2000RawIO.__init__(self, filename=filename)
diff --git a/neo/io/brainvisionio.py b/neo/io/brainvisionio.py
index 9d5ecb076..b50f299f3 100644
--- a/neo/io/brainvisionio.py
+++ b/neo/io/brainvisionio.py
@@ -5,7 +5,6 @@
 class BrainVisionIO(BrainVisionRawIO, BaseFromRaw):
     """Class for reading data from the BrainVision product."""
     _prefered_signal_group_mode = 'group-by-same-units'
-    _default_group_mode_have_change_in_0_9 = True
 
     def __init__(self, filename):
         BrainVisionRawIO.__init__(self, filename=filename)
diff --git a/neo/io/elanio.py b/neo/io/elanio.py
index 566f5f5b7..72d3a0ec9 100644
--- a/neo/io/elanio.py
+++ b/neo/io/elanio.py
@@ -25,7 +25,6 @@ class ElanIO(ElanRawIO, BaseFromRaw):
             to it
     """
     _prefered_signal_group_mode = 'group-by-same-units'
-    _default_group_mode_have_change_in_0_9 = True
 
     def __init__(self, filename, entfile=None, posfile=None):
         ElanRawIO.__init__(self, filename=filename, entfile=entfile,
diff --git a/neo/io/neuroexplorerio.py b/neo/io/neuroexplorerio.py
index e58e4e65c..fedeeef93 100644
--- a/neo/io/neuroexplorerio.py
+++ b/neo/io/neuroexplorerio.py
@@ -5,7 +5,6 @@
 class NeuroExplorerIO(NeuroExplorerRawIO, BaseFromRaw):
     """Class for reading data from NeuroExplorer (.nex)"""
     _prefered_signal_group_mode = 'group-by-same-units'
-    _default_group_mode_have_change_in_0_9 = True
 
     def __init__(self, filename):
         NeuroExplorerRawIO.__init__(self, filename=filename)
diff --git a/neo/io/plexonio.py b/neo/io/plexonio.py
index 26d1e2649..5db0d648f 100644
--- a/neo/io/plexonio.py
+++ b/neo/io/plexonio.py
@@ -14,7 +14,6 @@ class PlexonIO(PlexonRawIO, BaseFromRaw):
     Other versions have not been tested.
     """
     _prefered_signal_group_mode = 'group-by-same-units'
-    _default_group_mode_have_change_in_0_9 = True
 
     def __init__(self, filename):
         PlexonRawIO.__init__(self, filename=filename)
diff --git a/neo/io/rawbinarysignalio.py b/neo/io/rawbinarysignalio.py
index 58494c2f3..7f8b30bf4 100644
--- a/neo/io/rawbinarysignalio.py
+++ b/neo/io/rawbinarysignalio.py
@@ -41,7 +41,6 @@ class RawBinarySignalIO(RawBinarySignalRawIO, BaseFromRaw):
     """
 
     _prefered_signal_group_mode = 'group-by-same-units'
-    _default_group_mode_have_change_in_0_9 = True
 
     is_readable = True
     is_writable = True
diff --git a/neo/io/tdtio.py b/neo/io/tdtio.py
index 5ba2ccd56..1a3870a91 100644
--- a/neo/io/tdtio.py
+++ b/neo/io/tdtio.py
@@ -12,7 +12,6 @@ class TdtIO(TdtRawIO, BaseFromRaw):
     Tanks correspond to Neo Blocks and TDT blocks correspond to Neo Segments.
     """
     _prefered_signal_group_mode = 'group-by-same-units'
-    _default_group_mode_have_change_in_0_9 = True
     mode = 'dir'
 
     def __init__(self, dirname):
diff --git a/neo/io/winedrio.py b/neo/io/winedrio.py
index a304f8045..1d94ef193 100644
--- a/neo/io/winedrio.py
+++ b/neo/io/winedrio.py
@@ -11,7 +11,6 @@ class WinEdrIO(WinEdrRawIO, BaseFromRaw):
     http://spider.science.strath.ac.uk/sipbs/software.htm
     """
     _prefered_signal_group_mode = 'group-by-same-units'
-    _default_group_mode_have_change_in_0_9 = True
 
     def __init__(self, filename):
         WinEdrRawIO.__init__(self, filename=filename)
diff --git a/neo/io/winwcpio.py b/neo/io/winwcpio.py
index 3b1197aec..f947c9911 100644
--- a/neo/io/winwcpio.py
+++ b/neo/io/winwcpio.py
@@ -11,7 +11,6 @@ class WinWcpIO(WinWcpRawIO, BaseFromRaw):
     http://spider.science.strath.ac.uk/sipbs/software.htm
     """
     _prefered_signal_group_mode = 'group-by-same-units'
-    _default_group_mode_have_change_in_0_9 = True
 
     def __init__(self, filename):
         WinWcpRawIO.__init__(self, filename=filename)