diff --git a/tools/build_api.py b/tools/build_api.py
index 6bdf5a1726..8b403d5f8c 100644
--- a/tools/build_api.py
+++ b/tools/build_api.py
@@ -201,7 +201,7 @@ def is_official_target(target_name, version):
             # For version 5, ARM, GCC_ARM, and IAR toolchain support is required
             required_toolchains = [
                 set(['ARM', 'GCC_ARM', 'IAR']),
-                set(['ARMC6', 'GCC_ARM', 'IAR'])
+                set(['ARMC6'])
             ]
             supported_toolchains = set(target.supported_toolchains)