diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8078f2e6..20c7e88d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,8 @@
 - explorer: enforce max column width Features and Editor panes #691 @mike-hunhoff
 - explorer: add option to limit features to currently selected disassembly address #692 @mike-hunhoff
 - all: add support for ELF files #700 @Adir-Shemesh @TcM1911
+- rule format: add characteristic for file format, like `format/pe` @williballenthin
+- rule format: add characteristic for operating system, like `os/windows` @701 @williballenthin
 
 ### Breaking Changes