diff --git a/js/grunt/reportUnusedStrings.ts b/js/grunt/reportUnusedStrings.ts
index 4a0c734c..e4a0edad 100644
--- a/js/grunt/reportUnusedStrings.ts
+++ b/js/grunt/reportUnusedStrings.ts
@@ -1,4 +1,4 @@
-// Copyright 2015-2021, University of Colorado Boulder
+// Copyright 2015-2024, University of Colorado Boulder
 
 /**
  * Report which translatable strings from a sim were not used in the simulation with a require statement.
diff --git a/js/grunt/tasks/check.ts b/js/grunt/tasks/check.ts
index 433448e1..c6359a44 100644
--- a/js/grunt/tasks/check.ts
+++ b/js/grunt/tasks/check.ts
@@ -1,4 +1,4 @@
-// Copyright 2013-2024, University of Colorado Boulder
+// Copyright 2024, University of Colorado Boulder
 
 /**
  * Type checks *.ts files. Named after deno check. Automatically uses -b as appropriate.