diff --git a/NEWS.md b/NEWS.md
index 15d316e..bfbb82e 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,3 +1,11 @@
+1.0.4 (2016-07-26)
+
+__Bugfixes__
+
+* Always default arguments to `NULL`, which prevents duplication & overwrite by
+  dataservices-api
+  ([#173](https://github.com/CartoDB/observatory-extension/issues/173))
+
 1.0.3 (2016-07-25)
 
 __Bugfixes__
diff --git a/src/pg/observatory.control b/src/pg/observatory.control
index a97eced..20d9a45 100644
--- a/src/pg/observatory.control
+++ b/src/pg/observatory.control
@@ -1,5 +1,5 @@
 comment = 'CartoDB Observatory backend extension'
-default_version = '1.0.3'
+default_version = '1.0.4'
 requires = 'postgis, postgres_fdw'
 superuser = true
 schema = cdb_observatory
diff --git a/src/pg/sql/44_observatory_geometries.sql b/src/pg/sql/44_observatory_geometries.sql
index 0ca42d4..dd962f9 100644
--- a/src/pg/sql/44_observatory_geometries.sql
+++ b/src/pg/sql/44_observatory_geometries.sql
@@ -244,7 +244,7 @@ CREATE OR REPLACE FUNCTION cdb_observatory._OBS_GetBoundariesByGeometry(
   geom geometry(Geometry, 4326),
   boundary_id text,
   time_span text DEFAULT NULL,
-  overlap_type text DEFAULT 'intersects')
+  overlap_type text DEFAULT NULL)
 RETURNS TABLE(the_geom geometry, geom_refs text)
 AS $$
 DECLARE
@@ -253,7 +253,7 @@ DECLARE
   geoid_colname text;
   target_table text;
 BEGIN
-
+  overlap_type := COALESCE(overlap_type, 'intersects');
   -- check inputs
   IF lower(overlap_type) NOT IN ('contains', 'intersects', 'within')
   THEN
@@ -318,7 +318,7 @@ CREATE OR REPLACE FUNCTION cdb_observatory.OBS_GetBoundariesByGeometry(
   geom geometry(Geometry, 4326),
   boundary_id text,
   time_span text DEFAULT NULL,
-  overlap_type text DEFAULT 'intersects')
+  overlap_type text DEFAULT NULL)
 RETURNS TABLE(the_geom geometry, geom_refs text)
 AS $$
 BEGIN
@@ -364,7 +364,7 @@ CREATE OR REPLACE FUNCTION cdb_observatory.OBS_GetBoundariesByPointAndRadius(
   radius numeric, -- radius in meters
   boundary_id text,
   time_span text DEFAULT NULL,
-  overlap_type text DEFAULT 'intersects')
+  overlap_type text DEFAULT NULL)
 RETURNS TABLE(the_geom geometry, geom_refs text)
 AS $$
 DECLARE
@@ -382,7 +382,8 @@ BEGIN
                FROM cdb_observatory._OBS_GetBoundariesByGeometry(
                         circle_boundary,
                         boundary_id,
-                        time_span);
+                        time_span,
+                        overlap_type);
   RETURN;
 END;
 $$ LANGUAGE plpgsql;
@@ -394,7 +395,7 @@ CREATE OR REPLACE FUNCTION cdb_observatory._OBS_GetPointsByGeometry(
   geom geometry(Geometry, 4326),
   boundary_id text,
   time_span text DEFAULT NULL,
-  overlap_type text DEFAULT 'intersects')
+  overlap_type text DEFAULT NULL)
 RETURNS TABLE(the_geom geometry, geom_refs text)
 AS $$
 DECLARE
@@ -403,6 +404,7 @@ DECLARE
   geoid_colname text;
   target_table text;
 BEGIN
+  overlap_type := COALESCE(overlap_type, 'intersects');
 
   IF lower(overlap_type) NOT IN ('contains', 'within', 'intersects')
   THEN
@@ -464,7 +466,7 @@ CREATE OR REPLACE FUNCTION cdb_observatory.OBS_GetPointsByGeometry(
   geom geometry(Geometry, 4326),
   boundary_id text,
   time_span text DEFAULT NULL,
-  overlap_type text DEFAULT 'intersects')
+  overlap_type text DEFAULT NULL)
 RETURNS TABLE(the_geom geometry, geom_refs text)
 AS $$
 BEGIN
@@ -509,7 +511,7 @@ CREATE OR REPLACE FUNCTION cdb_observatory.OBS_GetPointsByPointAndRadius(
   radius numeric, -- radius in meters
   boundary_id text,
   time_span text DEFAULT NULL,
-  overlap_type text DEFAULT 'intersects')
+  overlap_type text DEFAULT NULL)
 RETURNS TABLE(the_geom geometry, geom_refs text)
 AS $$
 DECLARE