diff --git a/source/phenopacket-schema-1.0.0-RC3/requirements.txt b/source/phenopacket-schema-1.0.0-RC3/requirements.txt
index 5fab709..c89f3b9 100644
--- a/source/phenopacket-schema-1.0.0-RC3/requirements.txt
+++ b/source/phenopacket-schema-1.0.0-RC3/requirements.txt
@@ -1,2 +1,2 @@
-protobuf==3.7.1
+protobuf==3.15.0
 xmltodict==0.12.0
\ No newline at end of file