diff --git a/buf/registry/module/v1/commit.proto b/buf/registry/module/v1/commit.proto
index d298a36..646c68f 100644
--- a/buf/registry/module/v1/commit.proto
+++ b/buf/registry/module/v1/commit.proto
@@ -75,4 +75,14 @@ message Commit {
     (buf.validate.field).string.max_len = 255,
     (buf.validate.field).ignore = IGNORE_IF_UNPOPULATED
   ];
+  // The SPDX License Identifier of the Commit.
+  //
+  // May be empty if the SPDX License Identifier was not explicitly set during upload, if the
+  // license file was not present, or if it was not possible to detect the SPDX License Identifier
+  // from the license file.
+  string spdx_license_id = 8 [
+    (buf.validate.field).string.min_len = 1,
+    (buf.validate.field).string.pattern = "^[a-zA-Z0-9-.+]+$",
+    (buf.validate.field).ignore = IGNORE_IF_UNPOPULATED
+  ];
 }
diff --git a/buf/registry/module/v1/upload_service.proto b/buf/registry/module/v1/upload_service.proto
index 13ac585..e21f567 100644
--- a/buf/registry/module/v1/upload_service.proto
+++ b/buf/registry/module/v1/upload_service.proto
@@ -61,6 +61,13 @@ message UploadRequest {
       (buf.validate.field).string.max_len = 255,
       (buf.validate.field).ignore = IGNORE_IF_UNPOPULATED
     ];
+    // The SPDX License Identifier. If this field is not set, the SPDX License Identifier will be
+    // detected from the license file, if present.
+    string spdx_license_id = 5 [
+      (buf.validate.field).string.min_len = 1,
+      (buf.validate.field).string.pattern = "^[a-zA-Z0-9-.+]+$",
+      (buf.validate.field).ignore = IGNORE_IF_UNPOPULATED
+    ];
   }
   // The Contents of all references.
   repeated Content contents = 1 [(buf.validate.field).repeated.min_items = 1];
diff --git a/buf/registry/module/v1beta1/commit.proto b/buf/registry/module/v1beta1/commit.proto
index 5a8e6d2..2a2d627 100644
--- a/buf/registry/module/v1beta1/commit.proto
+++ b/buf/registry/module/v1beta1/commit.proto
@@ -75,4 +75,14 @@ message Commit {
     (buf.validate.field).string.max_len = 255,
     (buf.validate.field).ignore = IGNORE_IF_UNPOPULATED
   ];
+  // The SPDX License Identifier of the Commit.
+  //
+  // May be empty if the SPDX License Identifier was not explicitly set during upload, if the
+  // license file was not present, or if it was not possible to detect the SPDX License Identifier
+  // from the license file.
+  string spdx_license_id = 8 [
+    (buf.validate.field).string.min_len = 1,
+    (buf.validate.field).string.pattern = "^[a-zA-Z0-9-.+]+$",
+    (buf.validate.field).ignore = IGNORE_IF_UNPOPULATED
+  ];
 }
diff --git a/buf/registry/module/v1beta1/upload_service.proto b/buf/registry/module/v1beta1/upload_service.proto
index 2333365..b2f5549 100644
--- a/buf/registry/module/v1beta1/upload_service.proto
+++ b/buf/registry/module/v1beta1/upload_service.proto
@@ -74,6 +74,13 @@ message UploadRequest {
       (buf.validate.field).string.max_len = 255,
       (buf.validate.field).ignore = IGNORE_IF_UNPOPULATED
     ];
+    // The SPDX License Identifier. If this field is not set, the SPDX License Identifier will be
+    // detected from the license file, if present.
+    string spdx_license_id = 5 [
+      (buf.validate.field).string.min_len = 1,
+      (buf.validate.field).string.pattern = "^[a-zA-Z0-9-.+]+$",
+      (buf.validate.field).ignore = IGNORE_IF_UNPOPULATED
+    ];
   }
   // The Contents of all references.
   repeated Content contents = 1 [(buf.validate.field).repeated.min_items = 1];