diff --git a/MODULE.bazel b/MODULE.bazel
index 1217d43d..d55deab9 100644
--- a/MODULE.bazel
+++ b/MODULE.bazel
@@ -9,7 +9,6 @@ bazel_dep(name = "bazel_skylib", version = "1.4.2")
 bazel_dep(name = "rules_java", version = "6.3.0")
 bazel_dep(name = "rules_jvm_external", version = "5.2")
 bazel_dep(name = "rules_license", version = "0.0.7")
-bazel_dep(name = "protobuf", version = "21.7", repo_name = "com_google_protobuf")
 
 # Maven artifacts required by Stardoc; keep consistent with deps.bzl
 STARDOC_MAVEN_ARTIFACTS = [
diff --git a/src/main/java/com/google/devtools/build/skydoc/renderer/BUILD b/src/main/java/com/google/devtools/build/skydoc/renderer/BUILD
index 69a08f36..5ccec659 100644
--- a/src/main/java/com/google/devtools/build/skydoc/renderer/BUILD
+++ b/src/main/java/com/google/devtools/build/skydoc/renderer/BUILD
@@ -32,7 +32,6 @@ java_library(
     deps = [
         "//src/main/java/com/google/devtools/build/skydoc/rendering",
         "//stardoc/proto:stardoc_output_java_proto",
-        "@com_google_protobuf//:protobuf_java",
         "@stardoc_maven//:com_beust_jcommander",
         "@stardoc_maven//:com_google_guava_guava",
     ],
diff --git a/src/main/java/com/google/devtools/build/skydoc/renderer/RendererMain.java b/src/main/java/com/google/devtools/build/skydoc/renderer/RendererMain.java
index d7ececa7..c021d0ca 100644
--- a/src/main/java/com/google/devtools/build/skydoc/renderer/RendererMain.java
+++ b/src/main/java/com/google/devtools/build/skydoc/renderer/RendererMain.java
@@ -33,8 +33,6 @@
 import com.google.devtools.build.skydoc.rendering.proto.StardocOutputProtos.RepositoryRuleInfo;
 import com.google.devtools.build.skydoc.rendering.proto.StardocOutputProtos.RuleInfo;
 import com.google.devtools.build.skydoc.rendering.proto.StardocOutputProtos.StarlarkFunctionInfo;
-import com.google.protobuf.ExtensionRegistry;
-import com.google.protobuf.InvalidProtocolBufferException;
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.PrintWriter;
@@ -81,9 +79,7 @@ public void println() {
             write("\n");
           }
         }) {
-      ModuleInfo moduleInfo =
-          ModuleInfo.parseFrom(
-              new FileInputStream(inputPath), ExtensionRegistry.getEmptyRegistry());
+      ModuleInfo moduleInfo = ModuleInfo.parseFrom(new FileInputStream(inputPath));
 
       MarkdownRenderer renderer =
           new MarkdownRenderer(
@@ -161,8 +157,14 @@ public void println() {
         printWriter.println(renderer.renderMarkdownFooter(moduleInfo));
       }
 
-    } catch (InvalidProtocolBufferException e) {
-      throw new IllegalArgumentException("Input file is not a valid ModuleInfo proto.", e);
+    } catch (IOException e) {
+      // Avoid an explicit dependency on the Java protobuf runtime as it should be injected by the
+      // root module via a proto_lang_toolchain.
+      if (e.getClass().getName().equals("com.google.protobuf.InvalidProtocolBufferException")) {
+        throw new IllegalArgumentException("Input file is not a valid ModuleInfo proto.", e);
+      } else {
+        throw e;
+      }
     }
   }