diff --git a/cpp/ql/src/Critical/LargeParameter.ql b/cpp/ql/src/Critical/LargeParameter.ql
index 1571e96bbec9..c2fd1053ae07 100644
--- a/cpp/ql/src/Critical/LargeParameter.ql
+++ b/cpp/ql/src/Critical/LargeParameter.ql
@@ -18,6 +18,7 @@ where f.getAParameter() = p
   and t.getSize() = size
   and size > 64
   and not t.getUnderlyingType() instanceof ArrayType
+  and not f instanceof CopyAssignmentOperator
 select
   p, "This parameter of type $@ is " + size.toString() + " bytes - consider passing a pointer/reference instead.",
   t, t.toString()
diff --git a/cpp/ql/test/query-tests/Critical/LargeParameter/test.cpp b/cpp/ql/test/query-tests/Critical/LargeParameter/test.cpp
index 334eeadf4484..cc9c217f9f9e 100644
--- a/cpp/ql/test/query-tests/Critical/LargeParameter/test.cpp
+++ b/cpp/ql/test/query-tests/Critical/LargeParameter/test.cpp
@@ -44,3 +44,11 @@ void myFunction2(mySmallStruct *a, myLargeStruct *b) // GOOD
 void myFunction3(mySmallStruct &a, myLargeStruct &b) // GOOD
 {
 }
+
+struct CustomAssignmentOp {
+  // GOOD: it's an accepted pattern to implement copy assignment via copy and
+  // swap. This delegates the resource management involved in copying to the
+  // copy constructor so that logic only has to be written once.
+  CustomAssignmentOp &operator=(CustomAssignmentOp rhs);
+  char data[4096];
+};