diff --git a/pcbnew/dialogs/panel_setup_rules_help.md b/pcbnew/dialogs/panel_setup_rules_help.md
index cf75729ab4..01756aa1ba 100644
--- a/pcbnew/dialogs/panel_setup_rules_help.md
+++ b/pcbnew/dialogs/panel_setup_rules_help.md
@@ -119,7 +119,12 @@ True if `A` has a net that is part of a differential pair.
     A.inDiffPair('<net_name>')
 True if `A` has net that is part of the specified differential pair.
 `<net_name>` is the base name of the differential pair.  For example, `inDiffPair('CLK')`
-matches items in the `CLK_P` and `CLK_N` nets.<br>
+matches items in the `CLK_P` and `CLK_N` nets.
+<br><br>
+
+    A.isCoupledDiffPair()
+True if `A` and `B` are members of the same diff pair.
+<br><br>
 
     A.memberOf('<group_name>')
 True if `A` is a member of the given group. Includes nested membership.
diff --git a/pcbnew/drc/drc_engine.cpp b/pcbnew/drc/drc_engine.cpp
index 4811f7a3df..b2c60be9e0 100644
--- a/pcbnew/drc/drc_engine.cpp
+++ b/pcbnew/drc/drc_engine.cpp
@@ -295,9 +295,7 @@ void DRC_ENGINE::loadImplicitRules()
                                                              ncName );
                     netclassRule->m_Implicit = true;
 
-                    expr = wxString::Format( "A.NetClass == '%s' && A.isDiffPair() "
-                                             "&& B.NetClass == '%s' && B.isDiffPair()",
-                                             ncName,
+                    expr = wxString::Format( "A.NetClass == '%s' && A.isCoupledDiffPair()",
                                              ncName );
                     netclassRule->m_Condition = new DRC_RULE_CONDITION( expr );
                     netclassItemSpecificRules.push_back( netclassRule );
diff --git a/pcbnew/pcb_expr_evaluator.cpp b/pcbnew/pcb_expr_evaluator.cpp
index 8608b5b904..fecb65202b 100644
--- a/pcbnew/pcb_expr_evaluator.cpp
+++ b/pcbnew/pcb_expr_evaluator.cpp
@@ -728,6 +728,30 @@ static void isDiffPair( LIBEVAL::CONTEXT* aCtx, void* self )
 }
 
 
+static void isCoupledDiffPair( LIBEVAL::CONTEXT* aCtx, void* self )
+{
+    PCB_EXPR_CONTEXT*     context = static_cast<PCB_EXPR_CONTEXT*>( aCtx );
+    BOARD_CONNECTED_ITEM* a = dynamic_cast<BOARD_CONNECTED_ITEM*>( context->GetItem( 0 ) );
+    BOARD_CONNECTED_ITEM* b = dynamic_cast<BOARD_CONNECTED_ITEM*>( context->GetItem( 1 ) );
+    LIBEVAL::VALUE*       result = aCtx->AllocValue();
+
+    result->Set( 0.0 );
+    aCtx->Push( result );
+
+    if( a && b )
+    {
+        NETINFO_ITEM* netinfo = a->GetNet();
+        wxString      coupledNet, dummy;
+
+        if( netinfo && DRC_ENGINE::MatchDpSuffix( netinfo->GetNetname(), coupledNet, dummy ) != 0 )
+        {
+            if( b->GetNetname() == coupledNet )
+                result->Set( 1.0 );
+        }
+    }
+}
+
+
 static void inDiffPair( LIBEVAL::CONTEXT* aCtx, void* self )
 {
     LIBEVAL::VALUE*   arg    = aCtx->Pop();
@@ -783,6 +807,7 @@ void PCB_EXPR_BUILTIN_FUNCTIONS::RegisterAllFunctions()
     RegisterFunc( "memberOf('x')", memberOf );
     RegisterFunc( "fromTo('x','y')", exprFromTo );
     RegisterFunc( "isDiffPair()", isDiffPair );
+    RegisterFunc( "isCoupledDiffPair()", isCoupledDiffPair );
     RegisterFunc( "inDiffPair('x')", inDiffPair );
 }