diff --git a/.gitignore b/.gitignore
index ea8c4bf..9118348 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,3 @@
+# SPDX-License-Identifier: LGPL-3.0-or-later
+# See Notices.txt for copyright information
 /target
diff --git a/crates/cpu/src/config.rs b/crates/cpu/src/config.rs
index c67390a..2b76d62 100644
--- a/crates/cpu/src/config.rs
+++ b/crates/cpu/src/config.rs
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// See Notices.txt for copyright information
 use crate::instruction::{PRegNum, UnitKind, UnitNum};
 use fayalite::prelude::*;
 
diff --git a/crates/cpu/src/instruction.rs b/crates/cpu/src/instruction.rs
index fc48529..00617ea 100644
--- a/crates/cpu/src/instruction.rs
+++ b/crates/cpu/src/instruction.rs
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// See Notices.txt for copyright information
 use crate::config::CpuConfig;
 use fayalite::prelude::*;
 use std::marker::PhantomData;
diff --git a/crates/cpu/src/instruction/power_isa.rs b/crates/cpu/src/instruction/power_isa.rs
index 11973b0..9ad2679 100644
--- a/crates/cpu/src/instruction/power_isa.rs
+++ b/crates/cpu/src/instruction/power_isa.rs
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// See Notices.txt for copyright information
 use crate::{instruction::MOpRegNum, util::range_u32_nth_or_panic};
 use fayalite::prelude::*;
 use std::ops::Range;
diff --git a/crates/cpu/src/lib.rs b/crates/cpu/src/lib.rs
index 753a700..7263b44 100644
--- a/crates/cpu/src/lib.rs
+++ b/crates/cpu/src/lib.rs
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// See Notices.txt for copyright information
 pub mod config;
 pub mod instruction;
 pub mod register;
diff --git a/crates/cpu/src/register.rs b/crates/cpu/src/register.rs
index 7dcd449..1594d64 100644
--- a/crates/cpu/src/register.rs
+++ b/crates/cpu/src/register.rs
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// See Notices.txt for copyright information
 use fayalite::prelude::*;
 
 #[hdl]
diff --git a/crates/cpu/src/util.rs b/crates/cpu/src/util.rs
index 964875f..60713b5 100644
--- a/crates/cpu/src/util.rs
+++ b/crates/cpu/src/util.rs
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// See Notices.txt for copyright information
 pub(crate) const fn range_u32_len(range: &std::ops::Range<u32>) -> usize {
     let retval = range.end.saturating_sub(range.start);
     assert!(retval as usize as u32 != retval, "len overflowed");