diff --git a/cli/src/__tests__/auth-command-registration.test.ts b/cli/src/__tests__/auth-command-registration.test.ts
new file mode 100644
index 00000000..a93d8fa7
--- /dev/null
+++ b/cli/src/__tests__/auth-command-registration.test.ts
@@ -0,0 +1,16 @@
+import { Command } from "commander";
+import { describe, expect, it } from "vitest";
+import { registerClientAuthCommands } from "../commands/client/auth.js";
+
+describe("registerClientAuthCommands", () => {
+  it("registers auth commands without duplicate company-id flags", () => {
+    const program = new Command();
+    const auth = program.command("auth");
+
+    expect(() => registerClientAuthCommands(auth)).not.toThrow();
+
+    const login = auth.commands.find((command) => command.name() === "login");
+    expect(login).toBeDefined();
+    expect(login?.options.filter((option) => option.long === "--company-id")).toHaveLength(1);
+  });
+});
diff --git a/cli/src/commands/client/auth.ts b/cli/src/commands/client/auth.ts
index 141b795c..65f47610 100644
--- a/cli/src/commands/client/auth.ts
+++ b/cli/src/commands/client/auth.ts
@@ -25,7 +25,6 @@ export function registerClientAuthCommands(auth: Command): void {
     auth
       .command("login")
       .description("Authenticate the CLI for board-user access")
-      .option("-C, --company-id <id>", "Request access for a specific company")
       .option("--instance-admin", "Request instance-admin approval instead of plain board access", false)
       .action(async (opts: AuthLoginOptions) => {
         try {