diff --git a/include/openmc/capi.h b/include/openmc/capi.h
index 617153b6c..8815d243a 100644
--- a/include/openmc/capi.h
+++ b/include/openmc/capi.h
@@ -70,8 +70,8 @@ extern "C" {
   int openmc_next_batch(int* status);
   int openmc_nuclide_name(int index, const char** name);
   int openmc_plot_geometry();
-  int openmc_id_map(const void* slice, int32_t *data_out);
-  int openmc_property_map(const void* slice, double *data_out);
+  int openmc_id_map(const void* slice, int32_t* data_out);
+  int openmc_property_map(const void* slice, double* data_out);
   int openmc_reset();
   int openmc_run();
   void openmc_set_seed(int64_t new_seed);