diff --git a/migration/i1.0a-release/oracle/201302181158_IDEMPIERE-640.sql b/migration/i1.0a-release/oracle/201302181158_IDEMPIERE-640.sql
new file mode 100644
index 0000000000..24020f4c41
--- /dev/null
+++ b/migration/i1.0a-release/oracle/201302181158_IDEMPIERE-640.sql
@@ -0,0 +1,7 @@
+-- IDEMPIERE-640 Price List Versions must not allow duplicate valid from date
+CREATE UNIQUE INDEX m_pricelist_version_validfrom ON m_pricelist_version(m_pricelist_id, validfrom)
+;
+
+SELECT register_migration_script('201302181158_IDEMPIERE-640.sql') FROM dual
+;
+
diff --git a/migration/i1.0a-release/postgresql/201302181158_IDEMPIERE-640.sql b/migration/i1.0a-release/postgresql/201302181158_IDEMPIERE-640.sql
new file mode 100644
index 0000000000..24020f4c41
--- /dev/null
+++ b/migration/i1.0a-release/postgresql/201302181158_IDEMPIERE-640.sql
@@ -0,0 +1,7 @@
+-- IDEMPIERE-640 Price List Versions must not allow duplicate valid from date
+CREATE UNIQUE INDEX m_pricelist_version_validfrom ON m_pricelist_version(m_pricelist_id, validfrom)
+;
+
+SELECT register_migration_script('201302181158_IDEMPIERE-640.sql') FROM dual
+;
+