diff --git a/README b/README
index 2a301044..6055baea 100644
--- a/README
+++ b/README
@@ -296,7 +296,7 @@ covered.
 
 # The Hydra model is by LukeCEL.
 
-# The Arrokoth model is derived from the Spencer et al. 2020 model:
+# The Arrokoth model was converted to cmod from the Spencer et al. 2020 model:
     https://doi.org/10.6084/m9.figshare.11485443
 
 # The Psyche model is from Shepard et al. 2021: https://doi.org/10.3847/PSJ/abfdba
diff --git a/models/arrokoth.cmod.license b/models/arrokoth.cmod.license
new file mode 100644
index 00000000..013aa21e
--- /dev/null
+++ b/models/arrokoth.cmod.license
@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2020 John Spencer
+
+SPDX-License-Identifier: CC0-1.0