diff --git a/completions/bash/brew b/completions/bash/brew
index 3db0037f9d..d592c40207 100644
--- a/completions/bash/brew
+++ b/completions/bash/brew
@@ -1135,6 +1135,7 @@ _brew_install_bundler_gems() {
     -*)
       __brewcomp "
       --debug
+      --groups
       --help
       --quiet
       --verbose
diff --git a/completions/fish/brew.fish b/completions/fish/brew.fish
index a9b612517e..4478fad7f2 100644
--- a/completions/fish/brew.fish
+++ b/completions/fish/brew.fish
@@ -828,6 +828,7 @@ __fish_brew_complete_arg 'install; and not __fish_seen_argument -l formula -l fo
 
 __fish_brew_complete_cmd 'install-bundler-gems' 'Install Homebrew\'s Bundler gems'
 __fish_brew_complete_arg 'install-bundler-gems' -l debug -d 'Display any debugging information'
+__fish_brew_complete_arg 'install-bundler-gems' -l groups -d 'Installs the specified comma-separated list of gem groups (default: last used)'
 __fish_brew_complete_arg 'install-bundler-gems' -l help -d 'Show this message'
 __fish_brew_complete_arg 'install-bundler-gems' -l quiet -d 'Make some output more quiet'
 __fish_brew_complete_arg 'install-bundler-gems' -l verbose -d 'Make some output more verbose'
diff --git a/completions/zsh/_brew b/completions/zsh/_brew
index 7b79af79b4..5bd1340fd9 100644
--- a/completions/zsh/_brew
+++ b/completions/zsh/_brew
@@ -1016,6 +1016,7 @@ _brew_install() {
 _brew_install_bundler_gems() {
   _arguments \
     '--debug[Display any debugging information]' \
+    '--groups[Installs the specified comma-separated list of gem groups (default: last used)]' \
     '--help[Show this message]' \
     '--quiet[Make some output more quiet]' \
     '--verbose[Make some output more verbose]'
diff --git a/docs/Manpage.md b/docs/Manpage.md
index 82f26b9efa..e411907cab 100644
--- a/docs/Manpage.md
+++ b/docs/Manpage.md
@@ -1095,10 +1095,13 @@ Generate Homebrew's manpages and shell completions.
 * `--fail-if-not-changed`:
   Return a failing status code if no changes are detected in the manpage outputs. This can be used to notify CI when the manpages are out of date. Additionally, the date used in new manpages will match those in the existing manpages (to allow comparison without factoring in the date).
 
-### `install-bundler-gems`
+### `install-bundler-gems` [*`--groups`*`=`]
 
 Install Homebrew's Bundler gems.
 
+* `--groups`:
+  Installs the specified comma-separated list of gem groups (default: last used).
+
 ### `irb` [*`--examples`*] [*`--pry`*]
 
 Enter the interactive Homebrew Ruby shell.
diff --git a/manpages/brew.1 b/manpages/brew.1
index fc84829ba3..451355fc9d 100644
--- a/manpages/brew.1
+++ b/manpages/brew.1
@@ -1539,9 +1539,13 @@ Generate Homebrew\'s manpages and shell completions\.
 \fB\-\-fail\-if\-not\-changed\fR
 Return a failing status code if no changes are detected in the manpage outputs\. This can be used to notify CI when the manpages are out of date\. Additionally, the date used in new manpages will match those in the existing manpages (to allow comparison without factoring in the date)\.
 .
-.SS "\fBinstall\-bundler\-gems\fR"
+.SS "\fBinstall\-bundler\-gems\fR [\fI\-\-groups\fR\fB=\fR]"
 Install Homebrew\'s Bundler gems\.
 .
+.TP
+\fB\-\-groups\fR
+Installs the specified comma\-separated list of gem groups (default: last used)\.
+.
 .SS "\fBirb\fR [\fI\-\-examples\fR] [\fI\-\-pry\fR]"
 Enter the interactive Homebrew Ruby shell\.
 .