diff --git a/src/logger_io.c b/src/logger_io.c
index d421b0f3e82bba44037748c2204f457fee433536..dc3ca9b4909c844c6067738931b88c044e604313 100644
--- a/src/logger_io.c
+++ b/src/logger_io.c
@@ -114,8 +114,6 @@ void write_index_single(struct engine* e, const char* baseName,
 
   /* Write the relevant information */
   io_write_attribute(h_grp, "PeriodicBoundariesOn", INT, &periodic, 1);
-  int index = 1;
-  io_write_attribute(h_grp, "IsIndexFile", INT, &index, 1);
 
   /* Close runtime parameters */
   H5Gclose(h_grp);
diff --git a/src/single_io.c b/src/single_io.c
index 999afc1262817c683cbf71eb72e8adb0c67863c1..e8cd02ff8114f7b9de086ed44bdd124b6a01a338 100644
--- a/src/single_io.c
+++ b/src/single_io.c
@@ -686,8 +686,6 @@ void write_output_single(struct engine* e, const char* baseName,
 
   /* Write the relevant information */
   io_write_attribute(h_grp, "PeriodicBoundariesOn", INT, &periodic, 1);
-  int index = 0;
-  io_write_attribute(h_grp, "IsIndexFile", INT, &index, 1);
 
   /* Close runtime parameters */
   H5Gclose(h_grp);