diff --git a/firmware/include/gbb_header.h b/firmware/include/gbb_header.h
index 6a0b65fb54..7f9b0005c5 100644
--- a/firmware/include/gbb_header.h
+++ b/firmware/include/gbb_header.h
@@ -38,9 +38,11 @@
 /* BIOS should load option ROMs from arbitrary PCI devices. We'll never enable
  * this ourselves because it executes non-verified code, but if a customer wants
  * to void their warranty and set this flag in the read-only flash, they should
- * be able to do so.
- */
+ * be able to do so. */
 #define GBB_FLAG_LOAD_OPTION_ROMS         0x00000002
+/* The factory flow may need the BIOS to boot a non-ChromeOS kernel if the
+ * dev-switch is on. This flag allows that. */
+#define GBB_FLAG_ENABLE_ALTERNATE_OS      0x00000004
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/firmware/include/vboot_api.h b/firmware/include/vboot_api.h
index ffc0c41238..b9f9f4a620 100644
--- a/firmware/include/vboot_api.h
+++ b/firmware/include/vboot_api.h
@@ -186,6 +186,8 @@ typedef struct VbCommonParams {
 #define VB_INIT_OUT_S3_DEBUG_BOOT        0x00000010
 /* BIOS should load any PCI option ROMs it finds, not just internal video */
 #define VB_INIT_OUT_ENABLE_OPROM         0x00000020
+/* BIOS may be asked to boot something other than ChromeOS */
+#define VB_INIT_OUT_ENABLE_ALTERNATE_OS  0x00000040
 
 
 /* Data only used by VbInit() */
diff --git a/firmware/lib/vboot_api_init.c b/firmware/lib/vboot_api_init.c
index 7fa488ae32..f8c7490936 100644
--- a/firmware/lib/vboot_api_init.c
+++ b/firmware/lib/vboot_api_init.c
@@ -22,6 +22,7 @@ VbError_t VbInit(VbCommonParams* cparams, VbInitParams* iparams) {
   uint32_t recovery = VBNV_RECOVERY_NOT_REQUESTED;
   int is_s3_resume = 0;
   uint32_t s3_debug_boot = 0;
+  uint32_t user_enabled_custom_os = 0;
 
   VBDEBUG(("VbInit() input flags 0x%x\n", iparams->flags));
 
@@ -105,12 +106,27 @@ VbError_t VbInit(VbCommonParams* cparams, VbInitParams* iparams) {
     iparams->out_flags |= (VB_INIT_OUT_CLEAR_RAM |
                           VB_INIT_OUT_ENABLE_DISPLAY |
                           VB_INIT_OUT_ENABLE_USB_STORAGE);
+    /* ... which could include custom OSes */
+    VbNvGet(&vnc, VBNV_DEV_BOOT_CUSTOM, &user_enabled_custom_os);
+    if (user_enabled_custom_os)
+      iparams->out_flags |= VB_INIT_OUT_ENABLE_ALTERNATE_OS;
+  } else {
+    /* Normal mode, so disable dev_boot_* flags.  This ensures they will be
+     * initially disabled if the user later transitions back into developer
+     * mode. */
+    VbNvSet(&vnc, VBNV_DEV_BOOT_USB, 0);
+    VbNvSet(&vnc, VBNV_DEV_BOOT_CUSTOM, 0);
   }
 
   /* Allow BIOS to load arbitrary option ROMs? */
   if (gbb->flags & GBB_FLAG_LOAD_OPTION_ROMS)
     iparams->out_flags |= VB_INIT_OUT_ENABLE_OPROM;
 
+  /* The factory may need to boot custom OSes whenever the dev-switch is on */
+  if ((gbb->flags & GBB_FLAG_ENABLE_ALTERNATE_OS) &&
+      (iparams->flags & VB_INIT_FLAG_DEV_SWITCH_ON))
+    iparams->out_flags |= VB_INIT_OUT_ENABLE_ALTERNATE_OS;
+
   /* copy current recovery reason to shared data */
   shared->recovery_reason = (uint8_t)recovery;
 
diff --git a/firmware/lib/vboot_api_kernel.c b/firmware/lib/vboot_api_kernel.c
index fda5715af1..a013c8f23a 100644
--- a/firmware/lib/vboot_api_kernel.c
+++ b/firmware/lib/vboot_api_kernel.c
@@ -105,13 +105,6 @@ uint32_t VbTryLoadKernel(VbCommonParams* cparams, LoadKernelParams* p,
 
 /* Handle a normal boot. */
 VbError_t VbBootNormal(VbCommonParams* cparams, LoadKernelParams* p) {
-
-  /* Force dev_boot_* flags disabled.  This ensures they will be
-   * initially disabled if the user later transitions back into
-   * developer mode. */
-  VbNvSet(&vnc, VBNV_DEV_BOOT_USB, 0);
-  VbNvSet(&vnc, VBNV_DEV_BOOT_CUSTOM, 0);
-
   /* Boot from fixed disk only */
   return VbTryLoadKernel(cparams, p, VB_DISK_FLAG_FIXED);
 }