diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 3e71e8b33..c3b78ec11 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -91,7 +91,9 @@ repos:
         name: license header check (hawkeye)
         entry: hawkeye check --config licenserc.toml
         language: system
-        types_or: [rust, python, shell]
+        # One tag per extension family in licenserc.toml's `includes`; a type
+        # missing here means an edit touching only that type never runs the hook.
+        types_or: [rust, python, shell, powershell, markdown]
         pass_filenames: false
         groups: [local-tools] # runs in the dedicated `license-headers` CI job (hawkeye action)
 
diff --git a/install.ps1 b/install.ps1
index 0b42c2800..c325e36a6 100644
--- a/install.ps1
+++ b/install.ps1
@@ -1,3 +1,17 @@
+# Copyright © Advanced Micro Devices, Inc., or its affiliates.
+#
+# SPDX-License-Identifier: MIT
+
+# This file must stay BOM-less, so the "add a BOM" rule is suppressed for it.
+# The documented install path is `irm <url> | iex`, which hands the parser a
+# string rather than a file: a byte order mark survives into that string, the
+# parser glues it onto the first token, and the param() block below silently
+# stops being the script's first statement. All nine parameters then vanish,
+# with zero parse errors to show for it. The cost of staying BOM-less is that
+# Windows PowerShell 5.1 decodes this file as the ANSI codepage and renders the
+# © above as mojibake -- a cosmetic blemish in a comment, which is the cheaper
+# of the two failures. Do not "fix" this by adding a BOM.
+[Diagnostics.CodeAnalysis.SuppressMessageAttribute('PSUseBOMForUnicodeEncodedFile', '')]
 param(
     [Parameter(Position = 0)]
     [string] $Channel = $env:ROCM_CLI_CHANNEL,
diff --git a/licenserc.toml b/licenserc.toml
index 1e42e442c..c692e2fdc 100644
--- a/licenserc.toml
+++ b/licenserc.toml
@@ -15,6 +15,7 @@ includes = [
   "**/*.py",
   "**/*.sh",
   "**/*.md",
+  "**/*.ps1",
 ]
 
 excludes = [
@@ -27,3 +28,10 @@ excludes = [
 [[rules]]
 extensions = ["md"]
 style_out = "xml"
+
+## hawkeye has no built-in comment syntax for .ps1: without this rule the file is
+## reported `unsupported` and silently skipped (exit 0), so `includes` alone would
+## not enforce anything.
+[[rules]]
+extensions = ["ps1"]
+style_out = "script"