diff --git a/keyboards/melgeek/mj63/rev2/rules.mk b/keyboards/melgeek/mj63/rev2/rules.mk
index d5fc76b8e..c55beb7d1 100644
--- a/keyboards/melgeek/mj63/rev2/rules.mk
+++ b/keyboards/melgeek/mj63/rev2/rules.mk
@@ -1,5 +1,6 @@
 # MCU name
 MCU = STM32F303
+BOARD = QMK_PROTON_C
 
 # Build Options
 #   change yes to no to disable
diff --git a/keyboards/melgeek/mj64/rev3/rules.mk b/keyboards/melgeek/mj64/rev3/rules.mk
index 01b8aca41..f50aefd04 100644
--- a/keyboards/melgeek/mj64/rev3/rules.mk
+++ b/keyboards/melgeek/mj64/rev3/rules.mk
@@ -1,5 +1,6 @@
 # MCU name
 MCU = STM32F303
+BOARD = QMK_PROTON_C
 
 # Build Options
 #   change yes to no to disable
diff --git a/keyboards/melgeek/mj65/rev3/rules.mk b/keyboards/melgeek/mj65/rev3/rules.mk
index 57fea2c56..bf4ed9553 100644
--- a/keyboards/melgeek/mj65/rev3/rules.mk
+++ b/keyboards/melgeek/mj65/rev3/rules.mk
@@ -1,5 +1,6 @@
 # MCU name
 MCU = STM32F303
+BOARD = QMK_PROTON_C
 
 # Build Options
 #   change yes to no to disable