diff --git a/src/board/system76/darp7/espi.c b/src/board/system76/darp7/espi.c
index c6b0204..c69f8ed 100644
--- a/src/board/system76/darp7/espi.c
+++ b/src/board/system76/darp7/espi.c
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: GPL-3.0-only
+
 #include <8051.h>
 #include <stdint.h>
 
diff --git a/src/board/system76/darp7/include/board/espi.h b/src/board/system76/darp7/include/board/espi.h
index abc101a..684ef53 100644
--- a/src/board/system76/darp7/include/board/espi.h
+++ b/src/board/system76/darp7/include/board/espi.h
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: GPL-3.0-only
+
 #ifndef _BOARD_ESPI_H
 #define _BOARD_ESPI_H
 
diff --git a/src/board/system76/galp5/espi.c b/src/board/system76/galp5/espi.c
index c6b0204..c69f8ed 100644
--- a/src/board/system76/galp5/espi.c
+++ b/src/board/system76/galp5/espi.c
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: GPL-3.0-only
+
 #include <8051.h>
 #include <stdint.h>
 
diff --git a/src/board/system76/galp5/include/board/espi.h b/src/board/system76/galp5/include/board/espi.h
index abc101a..684ef53 100644
--- a/src/board/system76/galp5/include/board/espi.h
+++ b/src/board/system76/galp5/include/board/espi.h
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: GPL-3.0-only
+
 #ifndef _BOARD_ESPI_H
 #define _BOARD_ESPI_H
 
diff --git a/src/board/system76/lemp10/espi.c b/src/board/system76/lemp10/espi.c
index c6b0204..c69f8ed 100644
--- a/src/board/system76/lemp10/espi.c
+++ b/src/board/system76/lemp10/espi.c
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: GPL-3.0-only
+
 #include <8051.h>
 #include <stdint.h>
 
diff --git a/src/board/system76/lemp10/include/board/espi.h b/src/board/system76/lemp10/include/board/espi.h
index abc101a..684ef53 100644
--- a/src/board/system76/lemp10/include/board/espi.h
+++ b/src/board/system76/lemp10/include/board/espi.h
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: GPL-3.0-only
+
 #ifndef _BOARD_ESPI_H
 #define _BOARD_ESPI_H
 
diff --git a/src/ec/it5570e/espi.c b/src/ec/it5570e/espi.c
index 8c982c8..3ef87c9 100644
--- a/src/ec/it5570e/espi.c
+++ b/src/ec/it5570e/espi.c
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: GPL-3.0-only
+
 #include <common/debug.h>
 #include <ec/espi.h>