diff --git a/src/RWStepGeom/RWStepGeom_RWBSplineCurveWithKnots.cxx b/src/RWStepGeom/RWStepGeom_RWBSplineCurveWithKnots.cxx
index a3a31f722d..8911fcfc8f 100644
--- a/src/RWStepGeom/RWStepGeom_RWBSplineCurveWithKnots.cxx
+++ b/src/RWStepGeom/RWStepGeom_RWBSplineCurveWithKnots.cxx
@@ -76,13 +76,18 @@ void RWStepGeom_RWBSplineCurveWithKnots::ReadStep
 	Standard_Integer nsub3;
 	if (data->ReadSubList (num,3,"control_points_list",ach,nsub3)) {
 	  Standard_Integer nb3 = data->NbParams(nsub3);
-	  aControlPointsList = new StepGeom_HArray1OfCartesianPoint (1, nb3);
-	  for (Standard_Integer i3 = 1; i3 <= nb3; i3 ++) {
-	    //szv#4:S4163:12Mar99 `Standard_Boolean stat3 =` not needed
-	    if (data->ReadEntity (nsub3, i3,"cartesian_point", ach,
-				  STANDARD_TYPE(StepGeom_CartesianPoint), anent3))
-	      aControlPointsList->SetValue(i3, anent3);
-	  }
+    if(nb3 <1)
+      ach->AddFail("Number of control points of the b_spline_curve_form is equal to 0");
+    else
+    {
+      aControlPointsList = new StepGeom_HArray1OfCartesianPoint (1, nb3);
+      for (Standard_Integer i3 = 1; i3 <= nb3; i3 ++) {
+        //szv#4:S4163:12Mar99 `Standard_Boolean stat3 =` not needed
+        if (data->ReadEntity (nsub3, i3,"cartesian_point", ach,
+          STANDARD_TYPE(StepGeom_CartesianPoint), anent3))
+          aControlPointsList->SetValue(i3, anent3);
+      }
+    }
 	}
 
 	// --- inherited field : curveForm ---
diff --git a/src/STEPCAFControl/STEPCAFControl_Writer.cxx b/src/STEPCAFControl/STEPCAFControl_Writer.cxx
index 708e3e7299..93c8277dbb 100644
--- a/src/STEPCAFControl/STEPCAFControl_Writer.cxx
+++ b/src/STEPCAFControl/STEPCAFControl_Writer.cxx
@@ -889,8 +889,9 @@ static Standard_Integer FindEntities (const Handle(Transfer_FinderProcess) &FP,
       seqRI.Append (aLocalItem);
     }
   }
-  else
+  else if(!TransientListBinder.IsNull())
   {
+
     const Standard_Integer nb = TransientListBinder->NbTransients();
     for (Standard_Integer i=1; i<=nb; i++) {
       Handle(Standard_Transient) t = TransientListBinder->Transient(i);
diff --git a/src/StepToGeom/StepToGeom_MakeBSplineCurve.pxx b/src/StepToGeom/StepToGeom_MakeBSplineCurve.pxx
index 6933a838a2..043b419cab 100644
--- a/src/StepToGeom/StepToGeom_MakeBSplineCurve.pxx
+++ b/src/StepToGeom/StepToGeom_MakeBSplineCurve.pxx
@@ -43,7 +43,10 @@
       lastKnot = aKnots->Value(i);
     }
   }
-  
+  if(NbUniqueKnots <= 1)
+  {
+    return 0;
+  }
   TColStd_Array1OfReal Kn(1,NbUniqueKnots);
   TColStd_Array1OfInteger Mult(1,NbUniqueKnots);
   lastKnot = aKnots->Value(1);
@@ -83,6 +86,11 @@
   //aControlPointsList = new StepGeom_HArray1OfCartesianPoint(1,NbPoles);
   const Handle(StepGeom_HArray1OfCartesianPoint)& aControlPointsList = BSCW->ControlPointsList();
   Standard_Integer aSumMulDiff = aFMulDiff + aLMulDiff;
+  Standard_Integer nbP = NbPoles - aSumMulDiff;
+  if( nbP <= 0)
+  {
+     return 0;
+  }
   Array1OfPnt_gen Poles(1,NbPoles - aSumMulDiff);
   
   for (i = 1 + aFMulDiff; i<= NbPoles - aLMulDiff; ++i)
diff --git a/tests/bugs/step/bug27575 b/tests/bugs/step/bug27575
new file mode 100644
index 0000000000..e10b538237
--- /dev/null
+++ b/tests/bugs/step/bug27575
@@ -0,0 +1,16 @@
+puts "========"
+puts "OCC27575"
+puts "========"
+puts ""
+###########################################
+# Reading STEP file gives an empty result
+###########################################
+
+stepread [locate_data_file bug27575_Outer_Shell.stp] a *
+renamevar a_1 result
+
+whatis result
+
+checkshape result
+
+checkview -display result -2d -path ${imagedir}/${test_image}.png
diff --git a/tests/de/step_2/G5 b/tests/de/step_2/G5
index f5cd3c70c6..8ea589ef8a 100644
--- a/tests/de/step_2/G5
+++ b/tests/de/step_2/G5
@@ -1,17 +1,20 @@
 # !!!! This file is generated automatically, do not edit manually! See end script
+puts "TODO CR23096 ALL: NBSHAPES : Faulty" 
+
+
 set filename Inventor_iPartExample.stp
 
 set ref_data {
-DATA        : Faulties = 0  ( 0 )  Warnings = 0  ( 0 )  Summary  = 0  ( 0 )
-TPSTAT      : Faulties = 0  ( 16 )  Warnings = 0  ( 0 )  Summary  = 0  ( 16 )
+DATA        : Faulties = 0  ( 30 )  Warnings = 0  ( 0 )  Summary  = 0  ( 30 )
+TPSTAT      : Faulties = 0  ( 188 )  Warnings = 0  ( 96 )  Summary  = 0  ( 284 )
 CHECKSHAPE  : Wires    = 0  ( 0 )  Faces    = 0  ( 0 )  Shells   = 0  ( 0 )   Solids   = 0 ( 0 )
-NBSHAPES    : Solid    = 8  ( 8 )  Shell    = 8  ( 8 )  Face     = 517  ( 517 )   Summary  = 3521  ( 3521 )
-STATSHAPE   : Solid    = 8  ( 8 )  Shell    = 8  ( 8 )  Face     = 517  ( 517 )   FreeWire = 0  ( 0 )   FreeEdge  = 0 ( 0 )   SharedEdge = 1464  ( 1464 )
-TOLERANCE   : MaxTol   = 1.000100003e-007  ( 1.000100003e-007 )  AvgTol   =  1.00006193e-007  (  1.00006193e-007 )
-LABELS      : N0Labels = 9  ( 9 )  N1Labels = 11  ( 11 )  N2Labels = 0  ( 0 )   TotalLabels = 20  ( 20 )   NameLabels = 17  ( 17 )   ColorLabels = 8  ( 8 )   LayerLabels = 0  ( 0 )
+NBSHAPES    : Solid    = 8  ( 8 )  Shell    = 10  ( 44 )  Face     = 783  ( 817 )   Summary  = 5535  ( 5605 )
+STATSHAPE   : Solid    = 8  ( 8 )  Shell    = 10  ( 44 )  Face     = 783  ( 817 )   FreeWire = 0  ( 0 )   FreeEdge  = 0 ( 0 )   SharedEdge = 2330  ( 2330 )
+TOLERANCE   : MaxTol   = 0.0003647191536  ( 0.0003647191504 )  AvgTol   =  4.200927531e-005  (  4.190525894e-005 )
+LABELS      : N0Labels = 9  ( 9 )  N1Labels = 11  ( 11 )  N2Labels = 0  ( 0 )   TotalLabels = 20  ( 20 )   NameLabels = 17  ( 17 )   ColorLabels = 10  ( 10 )   LayerLabels = 0  ( 0 )
 PROPS       : Centroid = 0  ( 0 )  Volume   = 0  ( 0 )  Area     = 0  ( 0 )
-NCOLORS     : NColors  = 2  ( 2 )
-COLORS      : Colors   = GRAY66 SANDYBROWN  ( GRAY66 SANDYBROWN )
+NCOLORS     : NColors  = 3  ( 3 )
+COLORS      : Colors   = GOLDENROD3 GRAY66 SANDYBROWN  ( GOLDENROD3 GRAY66 SANDYBROWN )
 NLAYERS     : NLayers  = 0  ( 0 )
 LAYERS      : Layers   =   (  )