diff --git a/owlps-positioner/cfg/owlps-positioner.conf b/owlps-positioner/cfg/owlps-positioner.conf
index f82d127..14a6028 100644
--- a/owlps-positioner/cfg/owlps-positioner.conf
+++ b/owlps-positioner/cfg/owlps-positioner.conf
@@ -169,6 +169,14 @@ csv-file = /tmp/owlps-positioner.log
 # deleted. See also the replay option.
 #calibration-requests-timeout = 0
 
+# With this option activated, the calibration requests associated with
+# an existing reference point are deleted when receiving a new
+# calibration request, before to associate the new request with the
+# reference point.
+# The default is true, as there is generally no point keeping old
+# calibration requests.
+#unique-calibration-requests = true
+
 # If you activate the above option and want the calibration requests
 # to be treated as positioning requests (in addition to the normal
 # treatment of calibration requests), activate this option.
diff --git a/owlps-positioner/src/input.cc b/owlps-positioner/src/input.cc
index 8d58f38..5030508 100644
--- a/owlps-positioner/src/input.cc
+++ b/owlps-positioner/src/input.cc
@@ -148,7 +148,9 @@ const Request& Input::get_next_request() const
           const_cast<Request*>(&request)) ;
       if (calibration_request != NULL)
         {
-          calibration_request->reference_point_delete_requests() ;
+          if (Configuration::bool_value(
+                "positioning.unique-calibration-requests"))
+            calibration_request->reference_point_delete_requests() ;
           Stock::store_calibration_request(*calibration_request) ;
 
           if (Configuration::is_configured("verbose"))
diff --git a/owlps-positioner/src/userinterface.cc b/owlps-positioner/src/userinterface.cc
index d51dd2c..d54c68b 100644
--- a/owlps-positioner/src/userinterface.cc
+++ b/owlps-positioner/src/userinterface.cc
@@ -276,6 +276,10 @@ void UserInterface::fill_positioning_options()
    po::value<unsigned int>()->default_value(0),
    "Maximum age of a calibration request before to delete it"
    " (0 = unlimited). See also the \"replay\" option.")
+  ("positioning.unique-calibration-requests",
+   po::value<bool>()->default_value(true),
+   "Always delete existing former calibration requests when receiving"
+   " a new calibration request for an existing reference point.")
   ("positioning.position-calibration-requests",
    po::value<bool>()->default_value(false),
    "When accept-new-calibration-requests is activated, allow the"