diff --git a/socorro/signature/siglists/prefix_signature_re.txt b/socorro/signature/siglists/prefix_signature_re.txt
index 0e6bd52ecf..c93e2fad40 100644
--- a/socorro/signature/siglists/prefix_signature_re.txt
+++ b/socorro/signature/siglists/prefix_signature_re.txt
@@ -121,6 +121,7 @@ mozilla::ipc::RPCChannel::Call
 mozilla::ipc::RPCChannel::CxxStackFrame::CxxStackFrame
 mozilla::ipc::RPCChannel::EnteredCxxStack
 mozilla::ipc::RPCChannel::Send
+mozilla::ipc::WriteIPDLParam
 mozilla::layers::CompositorD3D11::Failed
 mozilla::layers::CompositorD3D11::HandleError
 mozilla::SpinEventLoopUntil<T>