diff --git a/open-vulnerability-clients/src/main/java/io/github/jeremylong/openvulnerability/client/nvd/NvdCveClientBuilder.java b/open-vulnerability-clients/src/main/java/io/github/jeremylong/openvulnerability/client/nvd/NvdCveClientBuilder.java
index 7ffc0f0c..47fa9a92 100644
--- a/open-vulnerability-clients/src/main/java/io/github/jeremylong/openvulnerability/client/nvd/NvdCveClientBuilder.java
+++ b/open-vulnerability-clients/src/main/java/io/github/jeremylong/openvulnerability/client/nvd/NvdCveClientBuilder.java
@@ -212,7 +212,8 @@ public NvdCveClientBuilder withFilter(BooleanFilter filter) {
     }
 
     /**
-     * Use a range of no more than 120 days on the last modified dates to filter the results.
+     * Use a range of no more than 120 days on the last modified dates to filter the results. The ZonedDateTime objects
+     * must be set to UTC.
      *
      * @param utcStartDate the UTC date time for the range start
      * @param utcEndDate the UTC date time for the range end
@@ -226,7 +227,7 @@ public NvdCveClientBuilder withLastModifiedFilter(ZonedDateTime utcStartDate, Zo
     }
 
     /**
-     * Filter the results with a range of published date times.
+     * Filter the results with a range of published date times. The ZonedDateTime objects must be set to UTC.
      *
      * @param utcStartDate the UTC date time for the range start
      * @param utcEndDate the UTC date time for the range end