diff --git a/tachyon/math/finite_fields/packed_prime_field32_avx2.h b/tachyon/math/finite_fields/packed_prime_field32_avx2.h
index e610abce4..0ed7d9bea 100644
--- a/tachyon/math/finite_fields/packed_prime_field32_avx2.h
+++ b/tachyon/math/finite_fields/packed_prime_field32_avx2.h
@@ -1,3 +1,8 @@
+// Copyright (c) 2022 The Plonky3 Authors
+// Use of this source code is governed by a MIT/Apache-2.0 style license that
+// can be found in the LICENSE-MIT.plonky3 and the LICENCE-APACHE.plonky3
+// file.
+
 #ifndef TACHYON_MATH_FINITE_FIELDS_PACKED_PRIME_FIELD32_AVX2_H_
 #define TACHYON_MATH_FINITE_FIELDS_PACKED_PRIME_FIELD32_AVX2_H_
 
diff --git a/tachyon/math/finite_fields/packed_prime_field32_avx512.h b/tachyon/math/finite_fields/packed_prime_field32_avx512.h
index 05bcd05f5..b157d9990 100644
--- a/tachyon/math/finite_fields/packed_prime_field32_avx512.h
+++ b/tachyon/math/finite_fields/packed_prime_field32_avx512.h
@@ -1,3 +1,8 @@
+// Copyright (c) 2022 The Plonky3 Authors
+// Use of this source code is governed by a MIT/Apache-2.0 style license that
+// can be found in the LICENSE-MIT.plonky3 and the LICENCE-APACHE.plonky3
+// file.
+
 #ifndef TACHYON_MATH_FINITE_FIELDS_PACKED_PRIME_FIELD32_AVX512_H_
 #define TACHYON_MATH_FINITE_FIELDS_PACKED_PRIME_FIELD32_AVX512_H_
 
diff --git a/tachyon/math/finite_fields/packed_prime_field32_neon.h b/tachyon/math/finite_fields/packed_prime_field32_neon.h
index 57c8416c2..daa828dc5 100644
--- a/tachyon/math/finite_fields/packed_prime_field32_neon.h
+++ b/tachyon/math/finite_fields/packed_prime_field32_neon.h
@@ -1,3 +1,8 @@
+// Copyright (c) 2022 The Plonky3 Authors
+// Use of this source code is governed by a MIT/Apache-2.0 style license that
+// can be found in the LICENSE-MIT.plonky3 and the LICENCE-APACHE.plonky3
+// file.
+
 #ifndef TACHYON_MATH_FINITE_FIELDS_PACKED_PRIME_FIELD32_NEON_H_
 #define TACHYON_MATH_FINITE_FIELDS_PACKED_PRIME_FIELD32_NEON_H_