diff --git a/image_analysis/WriteReflections.cpp b/image_analysis/WriteReflections.cpp
index 64361b47..e385f426 100644
--- a/image_analysis/WriteReflections.cpp
+++ b/image_analysis/WriteReflections.cpp
@@ -87,10 +87,9 @@ void WriteMmcifReflections(const std::vector<MergedReflection> &reflections,
     out << "#\n";
 
     // ---------- _software ----------
-    out << "_software.name         'Jungfraujoch'\n";
-
+    out << "_software.name         'Rugnux'\n";
     out << "_software.version      " << CifStr(jfjoch_version()) << "\n";
-    out << "_software.classification reduction\n";
+    out << "_software.classification 'data reduction'\n";
     out << "#\n";
 
     // ---------- _cell ----------
@@ -250,6 +249,10 @@ void WriteMtzReflections(const std::vector<MergedReflection> &reflections,
         experiment.GetSpaceGroupNumber().value_or(1));
     mtz.set_cell_for_all(unitCell);
 
+    // Producing-software provenance in the MTZ header (title + HISTORY, the CCP4 convention).
+    mtz.title = "Rugnux merged reflections";
+    mtz.history.push_back("From Rugnux " + jfjoch_version() + ", data reduction");
+
     // Add dataset
     gemmi::Mtz::Dataset& ds = mtz.add_dataset("native");
     ds.crystal_name = experiment.GetSampleName();