diff --git a/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/business/bo/PlaceholderPropertyCreator.java b/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/business/bo/PlaceholderPropertyCreator.java
index f5d56d2fb0eb928dc9de123ef1e88a52880a399d..b905307cb073e572841cee89440d473db34fe982 100644
--- a/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/business/bo/PlaceholderPropertyCreator.java
+++ b/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/business/bo/PlaceholderPropertyCreator.java
@@ -32,8 +32,8 @@ class PlaceholderPropertyCreator implements IPropertyPlaceholderCreator
     public void addDynamicPropertiesPlaceholders(Set<IEntityProperty> definedProperties,
             Set<String> dynamicProperties)
     {
-        addPlaceholders(definedProperties, dynamicProperties,
-                BasicConstant.DYNAMIC_PROPERTY_PLACEHOLDER_VALUE);
+        // Note: if you want to set the dynamicProperties to 'invalid', this is the right place
+        // to do it.
     }
 
     /**
diff --git a/openbis/source/sql/postgresql/091/function-091.sql b/openbis/source/sql/postgresql/091/function-091.sql
index c9c38b4f4e428969ed9086e3cf85414225366070..a6c4f33ac2989e4530ead550765dddc835fe3726 100644
--- a/openbis/source/sql/postgresql/091/function-091.sql
+++ b/openbis/source/sql/postgresql/091/function-091.sql
@@ -668,7 +668,6 @@ CREATE OR REPLACE RULE data_deleted_delete AS
 CREATE OR REPLACE RULE material_properties_update AS
     ON UPDATE TO material_properties 
     WHERE decode(substring(OLD.value from 1 for 1), 'escape') != E'\\xefbfbd'
-      AND decode(substring(NEW.value from 1 for 1), 'escape') != E'\\xefbfbd' 
     DO ALSO 
        INSERT INTO material_properties_history (
          ID, 
@@ -723,7 +722,6 @@ CREATE OR REPLACE RULE material_properties_delete AS
 CREATE OR REPLACE RULE experiment_properties_update AS
     ON UPDATE TO experiment_properties 
     WHERE decode(substring(OLD.value from 1 for 1), 'escape') != E'\\xefbfbd'
-      AND decode(substring(NEW.value from 1 for 1), 'escape') != E'\\xefbfbd' 
     DO ALSO 
        INSERT INTO experiment_properties_history (
          ID, 
@@ -778,7 +776,6 @@ CREATE OR REPLACE RULE experiment_properties_delete AS
 CREATE OR REPLACE RULE sample_properties_update AS
     ON UPDATE TO sample_properties
     WHERE decode(substring(OLD.value from 1 for 1), 'escape') != E'\\xefbfbd'
-      AND decode(substring(NEW.value from 1 for 1), 'escape') != E'\\xefbfbd' 
     DO ALSO
        INSERT INTO sample_properties_history (
          ID, 
@@ -833,7 +830,6 @@ CREATE OR REPLACE RULE sample_properties_delete AS
 CREATE OR REPLACE RULE data_set_properties_update AS
     ON UPDATE TO data_set_properties 
     WHERE decode(substring(OLD.value from 1 for 1), 'escape') != E'\\xefbfbd'
-      AND decode(substring(NEW.value from 1 for 1), 'escape') != E'\\xefbfbd' 
     DO ALSO
        INSERT INTO data_set_properties_history (
          ID, 
diff --git a/openbis/source/sql/postgresql/migration/migration-090-091.sql b/openbis/source/sql/postgresql/migration/migration-090-091.sql
index 59c4ff612b73d8667d9939b8fc8f67c0b95968cb..3d20724483e5007d53c8d1a6123714674e5cb716 100644
--- a/openbis/source/sql/postgresql/migration/migration-090-091.sql
+++ b/openbis/source/sql/postgresql/migration/migration-090-091.sql
@@ -75,7 +75,6 @@ ALTER TABLE material_properties_history ALTER COLUMN valid_from_timestamp SET NO
 CREATE OR REPLACE RULE material_properties_update AS
     ON UPDATE TO material_properties 
     WHERE decode(substring(OLD.value from 1 for 1), 'escape') != E'\\xefbfbd'
-      AND decode(substring(NEW.value from 1 for 1), 'escape') != E'\\xefbfbd' 
     DO ALSO 
        INSERT INTO material_properties_history (
          ID, 
@@ -130,7 +129,6 @@ CREATE OR REPLACE RULE material_properties_delete AS
 CREATE OR REPLACE RULE experiment_properties_update AS
     ON UPDATE TO experiment_properties 
     WHERE decode(substring(OLD.value from 1 for 1), 'escape') != E'\\xefbfbd'
-      AND decode(substring(NEW.value from 1 for 1), 'escape') != E'\\xefbfbd' 
     DO ALSO 
        INSERT INTO experiment_properties_history (
          ID, 
@@ -185,7 +183,6 @@ CREATE OR REPLACE RULE experiment_properties_delete AS
 CREATE OR REPLACE RULE sample_properties_update AS
     ON UPDATE TO sample_properties
     WHERE decode(substring(OLD.value from 1 for 1), 'escape') != E'\\xefbfbd'
-      AND decode(substring(NEW.value from 1 for 1), 'escape') != E'\\xefbfbd' 
     DO ALSO
        INSERT INTO sample_properties_history (
          ID, 
@@ -240,7 +237,6 @@ CREATE OR REPLACE RULE sample_properties_delete AS
 CREATE OR REPLACE RULE data_set_properties_update AS
     ON UPDATE TO data_set_properties 
     WHERE decode(substring(OLD.value from 1 for 1), 'escape') != E'\\xefbfbd'
-      AND decode(substring(NEW.value from 1 for 1), 'escape') != E'\\xefbfbd' 
     DO ALSO
        INSERT INTO data_set_properties_history (
          ID, 
diff --git a/openbis/sourceTest/sql/postgresql/091/finish-091.sql b/openbis/sourceTest/sql/postgresql/091/finish-091.sql
index 5d83ff73aaf76b383d43d39f8166eba4e0c7ddb1..2b3e88e648f9b7ecd80f7b65b4feef2638800210 100644
--- a/openbis/sourceTest/sql/postgresql/091/finish-091.sql
+++ b/openbis/sourceTest/sql/postgresql/091/finish-091.sql
@@ -306,7 +306,6 @@ CREATE RULE data_insert AS ON INSERT TO data DO INSTEAD INSERT INTO data_all (id
 CREATE RULE data_set_properties_update AS
     ON UPDATE TO data_set_properties 
     WHERE decode(substring(OLD.value from 1 for 1), 'escape') != E'\\xefbfbd'
-      AND decode(substring(NEW.value from 1 for 1), 'escape') != E'\\xefbfbd' 
     DO ALSO
        INSERT INTO data_set_properties_history (
          ID, 
@@ -362,7 +361,6 @@ CREATE RULE experiment_insert AS ON INSERT TO experiments DO INSTEAD INSERT INTO
 CREATE RULE experiment_properties_update AS
     ON UPDATE TO experiment_properties 
     WHERE decode(substring(OLD.value from 1 for 1), 'escape') != E'\\xefbfbd'
-      AND decode(substring(NEW.value from 1 for 1), 'escape') != E'\\xefbfbd' 
     DO ALSO 
        INSERT INTO experiment_properties_history (
          ID, 
@@ -416,7 +414,6 @@ CREATE RULE experiments_deleted_update AS ON UPDATE TO experiments_deleted DO IN
 CREATE RULE material_properties_update AS
     ON UPDATE TO material_properties 
     WHERE decode(substring(OLD.value from 1 for 1), 'escape') != E'\\xefbfbd'
-      AND decode(substring(NEW.value from 1 for 1), 'escape') != E'\\xefbfbd' 
     DO ALSO 
        INSERT INTO material_properties_history (
          ID, 
@@ -471,7 +468,6 @@ CREATE RULE sample_insert AS ON INSERT TO samples DO INSTEAD INSERT INTO samples
 CREATE RULE sample_properties_update AS
     ON UPDATE TO sample_properties
     WHERE decode(substring(OLD.value from 1 for 1), 'escape') != E'\\xefbfbd'
-      AND decode(substring(NEW.value from 1 for 1), 'escape') != E'\\xefbfbd' 
     DO ALSO
        INSERT INTO sample_properties_history (
          ID,