diff --git a/docs/tariff_plans.rst b/docs/tariff_plans.rst
index 9bed8cc73..8c9344837 100644
--- a/docs/tariff_plans.rst
+++ b/docs/tariff_plans.rst
@@ -300,3 +300,49 @@ MinutesWeight
     This field is used only if the balanceTag is MINUTES. If more minute balances are suitable for a call the one with smaller weight will be used first.
 Weight
     If there are multiple actions in a group, they will be executed in the order of their weight (smaller first).
+
+4.2.10. Derived Chargers
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+For each call we can bill more than one time, for that we need to use the
+following options:
+
++-----------+-------------+----------+---------+---------+--------------+-----------+--------------+----------------+-------------+---------------+--------------+--------------+------------------+----------------+-----------------+------------+
+| Direction |    Tenant   | Category | Account | Subject |    RunId     | RunFilter | ReqTypeField | DirectionField | TenantField | CategoryField | AccountField | SubjectField | DestinationField | SetupTimeField | AnswerTimeField | UsageField |
++===========+=============+==========+=========+=========+==============+===========+==============+================+=============+===============+==============+==============+==================+================+=================+============+
+|   \*out   | cgrates.org |   call   |   1001  |   1001  | derived_run1 |           |    ^rated    |   \*default    |  \*default  |   \*default   |  \*default   |    ^1002     |    \*default     |   \*default    |    \*default    | \*default  |
++-----------+-------------+----------+---------+---------+--------------+-----------+--------------+----------------+-------------+---------------+--------------+--------------+------------------+----------------+-----------------+------------+
+
+
+In derived charges we have 2 different kind of options, filters, and actions:
+
+Filters: With the following fields we filter the calls that need to run a extra
+billing parameter.
+    + Direction
+    + Tenant
+    + Category
+    + Account
+    + Subject
+
+Actions: In case of the filter options match, platform creates extra runid with
+the fields that we want to modify.
+
+    + RunId
+    + RunFilter
+    + ReqTypeField
+    + DirectionField
+    + TenantField
+    + CategoryField
+    + AccountField
+    + SubjectField
+    + DestinationField
+    + SetupTimeField
+    + AnswerTimeField
+    + UsageField
+
+In the example, all the calls with direction=out, tenant=cgrates.org,
+category="call" and account and subject equal 1001. Will be created a new cdr in
+the table *rated_cdrs* with the runID derived_run1, and the subject 1002.
+
+This feature it's useful in the case that you want to rated the calls 2 times,
+for example rated for different tenants or resellers.
diff --git a/engine/account.go b/engine/account.go
index 2b52cfead..fcb2a70c0 100644
--- a/engine/account.go
+++ b/engine/account.go
@@ -129,13 +129,15 @@ func (ub *Account) debitBalanceAction(a *Action, reset bool) error {
 		a.Balance.Value = -a.Balance.Value
 		a.Balance.dirty = true // Mark the balance as dirty since we have modified and it should be checked by action triggers
 		ub.BalanceMap[id] = append(ub.BalanceMap[id], a.Balance)
-		if a.Balance.SharedGroup != "" {
-			// add shared group member
-			sg, err := accountingStorage.GetSharedGroup(a.Balance.SharedGroup, false)
-			if err != nil || sg == nil {
-				//than problem
-				Logger.Warning(fmt.Sprintf("Could not get shared group: %v", a.Balance.SharedGroup))
-			} else {
+	}
+	if a.Balance.SharedGroup != "" {
+		// add shared group member
+		sg, err := accountingStorage.GetSharedGroup(a.Balance.SharedGroup, false)
+		if err != nil || sg == nil {
+			//than problem
+			Logger.Warning(fmt.Sprintf("Could not get shared group: %v", a.Balance.SharedGroup))
+		} else {
+			if !utils.IsSliceMember(sg.MemberIds, ub.Id) {
 				// add member and save
 				sg.MemberIds = append(sg.MemberIds, ub.Id)
 				accountingStorage.SetSharedGroup(sg)