diff --git a/include/libopencm3/stm32/desig.h b/include/libopencm3/stm32/desig.h
index 7b2eef7b..c7f3f65e 100644
--- a/include/libopencm3/stm32/desig.h
+++ b/include/libopencm3/stm32/desig.h
@@ -28,14 +28,6 @@
 /* Flash size register */
 #define DESIG_FLASH_SIZE		MMIO16(DESIG_FLASH_SIZE_BASE + 0x00)
 
-/* Unique ID register (96 bits) */
-/* Note: ST says these may be accessed in any width if you choose */
-#define DESIG_UID_15_0			MMIO16(DESIG_UNIQUE_ID_BASE + 0x00)
-/* Listed as "This field value is also reserved for a future feature" WTH?! */
-#define DESIG_UID_31_16			MMIO16(DESIG_UNIQUE_ID_BASE + 0x02)
-#define DESIG_UID_63_32			MMIO32(DESIG_UNIQUE_ID_BASE + 0x04)
-#define DESIG_UID_95_64			MMIO32(DESIG_UNIQUE_ID_BASE + 0x08)
-
 BEGIN_DECLS
 
 /**
diff --git a/include/libopencm3/stm32/f0/memorymap.h b/include/libopencm3/stm32/f0/memorymap.h
index 5122a23c..6bc74ed6 100644
--- a/include/libopencm3/stm32/f0/memorymap.h
+++ b/include/libopencm3/stm32/f0/memorymap.h
@@ -92,10 +92,11 @@
 
 #define GPIO_PORT_F_BASE		(PERIPH_BASE_AHB2 + 0x1400)
 
-
 /* Device Electronic Signature */
-/* ???
-#define DESIG_FLASH_SIZE_BASE           (INFO_BASE + 0x7e0)
-#define DESIG_UNIQUE_ID_BASE            (INFO_BASE + 0x7e8)
-*/
+#define DESIG_FLASH_SIZE_BASE		(0x1FFFF7CC)
+#define DESIG_UNIQUE_ID_BASE		(0x1FFFF7AC)
+#define DESIG_UNIQUE_ID0		MMIO32(DESIG_UNIQUE_ID_BASE)
+#define DESIG_UNIQUE_ID1		MMIO32(DESIG_UNIQUE_ID_BASE + 4)
+#define DESIG_UNIQUE_ID2		MMIO32(DESIG_UNIQUE_ID_BASE + 8)
+
 #endif
diff --git a/include/libopencm3/stm32/f1/memorymap.h b/include/libopencm3/stm32/f1/memorymap.h
index f909f6ed..29050c03 100644
--- a/include/libopencm3/stm32/f1/memorymap.h
+++ b/include/libopencm3/stm32/f1/memorymap.h
@@ -113,7 +113,12 @@
 #define FSMC_BASE			(PERIPH_BASE +  0x60000000)
 
 /* Device Electronic Signature */
-#define DESIG_FLASH_SIZE_BASE           (INFO_BASE + 0x7e0)
-#define DESIG_UNIQUE_ID_BASE            (INFO_BASE + 0x7e8)
+#define DESIG_FLASH_SIZE_BASE		(INFO_BASE + 0x7e0)
+#define DESIG_UNIQUE_ID_BASE		(INFO_BASE + 0x7e8)
+/* Ignore the "reserved for future use" half of the first word */
+#define DESIG_UNIQUE_ID0		MMIO32(DESIG_UNIQUE_ID_BASE)
+#define DESIG_UNIQUE_ID1		MMIO32(DESIG_UNIQUE_ID_BASE + 4)
+#define DESIG_UNIQUE_ID2		MMIO32(DESIG_UNIQUE_ID_BASE + 8)
+
 
 #endif
diff --git a/include/libopencm3/stm32/f2/memorymap.h b/include/libopencm3/stm32/f2/memorymap.h
index fd40b457..6aec2379 100644
--- a/include/libopencm3/stm32/f2/memorymap.h
+++ b/include/libopencm3/stm32/f2/memorymap.h
@@ -130,4 +130,12 @@
 /* PPIB */
 #define DBGMCU_BASE			(PPBI_BASE + 0x00042000)
 
+/* Device Electronic Signature */
+#define DESIG_FLASH_SIZE_BASE		(0x1FFF7A22)
+#define DESIG_UNIQUE_ID_BASE		(0x1FFF7A10)
+#define DESIG_UNIQUE_ID0		MMIO32(DESIG_UNIQUE_ID_BASE)
+#define DESIG_UNIQUE_ID1		MMIO32(DESIG_UNIQUE_ID_BASE + 4)
+#define DESIG_UNIQUE_ID2		MMIO32(DESIG_UNIQUE_ID_BASE + 8)
+
+
 #endif
diff --git a/include/libopencm3/stm32/f3/memorymap.h b/include/libopencm3/stm32/f3/memorymap.h
index 1b579f47..98aaee4e 100644
--- a/include/libopencm3/stm32/f3/memorymap.h
+++ b/include/libopencm3/stm32/f3/memorymap.h
@@ -114,4 +114,11 @@
 /* PPIB */
 #define DBGMCU_BASE			(PPBI_BASE + 0x00042000)
 
+/* Device Electronic Signature */
+#define DESIG_FLASH_SIZE_BASE		(0x1FFFF7CC)
+#define DESIG_UNIQUE_ID_BASE		(0x1FFFF7AC)
+#define DESIG_UNIQUE_ID0		MMIO32(DESIG_UNIQUE_ID_BASE)
+#define DESIG_UNIQUE_ID1		MMIO32(DESIG_UNIQUE_ID_BASE + 4)
+#define DESIG_UNIQUE_ID2		MMIO32(DESIG_UNIQUE_ID_BASE + 8)
+
 #endif
diff --git a/include/libopencm3/stm32/f4/memorymap.h b/include/libopencm3/stm32/f4/memorymap.h
index 5b1e6dbc..7065ce11 100644
--- a/include/libopencm3/stm32/f4/memorymap.h
+++ b/include/libopencm3/stm32/f4/memorymap.h
@@ -132,4 +132,11 @@
 /* PPIB */
 #define DBGMCU_BASE			(PPBI_BASE + 0x00042000)
 
+/* Device Electronic Signature */
+#define DESIG_FLASH_SIZE_BASE		(0x1FFF7A22)
+#define DESIG_UNIQUE_ID_BASE		(0x1FFF7A10)
+#define DESIG_UNIQUE_ID0		MMIO32(DESIG_UNIQUE_ID_BASE)
+#define DESIG_UNIQUE_ID1		MMIO32(DESIG_UNIQUE_ID_BASE + 4)
+#define DESIG_UNIQUE_ID2		MMIO32(DESIG_UNIQUE_ID_BASE + 8)
+
 #endif
diff --git a/include/libopencm3/stm32/l1/memorymap.h b/include/libopencm3/stm32/l1/memorymap.h
index 76a92738..8f0bc239 100644
--- a/include/libopencm3/stm32/l1/memorymap.h
+++ b/include/libopencm3/stm32/l1/memorymap.h
@@ -105,8 +105,11 @@
 #define AES_BASE			(PERIPH_BASE +  0x10000000)
 
 /* Device Electronic Signature */
-#define DESIG_FLASH_SIZE_BASE           (INFO_BASE + 0x8004C)
-#define DESIG_UNIQUE_ID_BASE            (INFO_BASE + 0x80050)
+#define DESIG_FLASH_SIZE_BASE		(INFO_BASE + 0x8004C)
+#define DESIG_UNIQUE_ID_BASE		(INFO_BASE + 0x80050)
+#define DESIG_UNIQUE_ID0		MMIO32(DESIG_UNIQUE_ID_BASE)
+#define DESIG_UNIQUE_ID1		MMIO32(DESIG_UNIQUE_ID_BASE + 4)
+#define DESIG_UNIQUE_ID2		MMIO32(DESIG_UNIQUE_ID_BASE + 0x14)
 
 /* Make the map names match those for other families to allow commonality */
 #define SPI1_I2S_BASE       SPI1_BASE
diff --git a/lib/stm32/desig.c b/lib/stm32/desig.c
index 89fb9294..b610e665 100644
--- a/lib/stm32/desig.c
+++ b/lib/stm32/desig.c
@@ -26,15 +26,9 @@ uint16_t desig_get_flash_size(void)
 
 void desig_get_unique_id(uint32_t result[])
 {
-	/* Could also just return a pointer to the start? read it as they wish?
-	 */
-	uint16_t bits15_0 = DESIG_UID_15_0;
-	uint32_t bits31_16 = DESIG_UID_31_16;
-	uint32_t bits63_32 = DESIG_UID_63_32;
-	uint32_t bits95_64 = DESIG_UID_95_64;
-	result[0] = bits95_64;
-	result[1] = bits63_32;
-	result[2] = bits31_16 << 16 | bits15_0;
+	result[0] = DESIG_UNIQUE_ID2;
+	result[1] = DESIG_UNIQUE_ID1;
+	result[2] = DESIG_UNIQUE_ID0;
 }
 
 void desig_get_unique_id_as_string(char *string,