diff --git a/crypto/asymmetric_keys/pkcs7.asn1 b/crypto/asymmetric_keys/pkcs7.asn1
index 1eca740..28e1f4a 100644
--- a/crypto/asymmetric_keys/pkcs7.asn1
+++ b/crypto/asymmetric_keys/pkcs7.asn1
@@ -1,3 +1,10 @@
+-- SPDX-License-Identifier: BSD-3-Clause
+--
+-- Copyright (C) 2009 IETF Trust and the persons identified as authors
+-- of the code
+--
+-- https://www.rfc-editor.org/rfc/rfc5652#section-3
+
 PKCS7ContentInfo ::= SEQUENCE {
 	contentType	ContentType ({ pkcs7_check_content_type }),
 	content		[0] EXPLICIT SignedData OPTIONAL
diff --git a/crypto/asymmetric_keys/pkcs8.asn1 b/crypto/asymmetric_keys/pkcs8.asn1
index 702c41a..a2a8af2 100644
--- a/crypto/asymmetric_keys/pkcs8.asn1
+++ b/crypto/asymmetric_keys/pkcs8.asn1
@@ -1,3 +1,9 @@
+-- SPDX-License-Identifier: BSD-3-Clause
+--
+-- Copyright (C) 2010 IETF Trust and the persons identified as authors
+-- of the code
+--
+-- https://www.rfc-editor.org/rfc/rfc5958#section-2
 --
 -- This is the unencrypted variant
 --
diff --git a/crypto/asymmetric_keys/x509.asn1 b/crypto/asymmetric_keys/x509.asn1
index 92d59c3..feb9573 100644
--- a/crypto/asymmetric_keys/x509.asn1
+++ b/crypto/asymmetric_keys/x509.asn1
@@ -1,3 +1,10 @@
+-- SPDX-License-Identifier: BSD-3-Clause
+--
+-- Copyright (C) 2008 IETF Trust and the persons identified as authors
+-- of the code
+--
+-- https://www.rfc-editor.org/rfc/rfc5280#section-4
+
 Certificate ::= SEQUENCE {
 	tbsCertificate		TBSCertificate ({ x509_note_tbs_certificate }),
 	signatureAlgorithm	AlgorithmIdentifier,
diff --git a/crypto/asymmetric_keys/x509_akid.asn1 b/crypto/asymmetric_keys/x509_akid.asn1
index 1a33231..164b2ed 100644
--- a/crypto/asymmetric_keys/x509_akid.asn1
+++ b/crypto/asymmetric_keys/x509_akid.asn1
@@ -1,3 +1,8 @@
+-- SPDX-License-Identifier: BSD-3-Clause
+--
+-- Copyright (C) 2008 IETF Trust and the persons identified as authors
+-- of the code
+--
 -- X.509 AuthorityKeyIdentifier
 -- rfc5280 section 4.2.1.1
 
diff --git a/crypto/rsaprivkey.asn1 b/crypto/rsaprivkey.asn1
index 4ce0675..76865124 100644
--- a/crypto/rsaprivkey.asn1
+++ b/crypto/rsaprivkey.asn1
@@ -1,3 +1,10 @@
+-- SPDX-License-Identifier: BSD-3-Clause
+--
+-- Copyright (C) 2016 IETF Trust and the persons identified as authors
+-- of the code
+--
+-- https://www.rfc-editor.org/rfc/rfc8017#appendix-A.1.2
+
 RsaPrivKey ::= SEQUENCE {
 	version		INTEGER,
 	n		INTEGER ({ rsa_get_n }),
diff --git a/crypto/rsapubkey.asn1 b/crypto/rsapubkey.asn1
index 725498e..0d32b1c 100644
--- a/crypto/rsapubkey.asn1
+++ b/crypto/rsapubkey.asn1
@@ -1,3 +1,10 @@
+-- SPDX-License-Identifier: BSD-3-Clause
+--
+-- Copyright (C) 2016 IETF Trust and the persons identified as authors
+-- of the code
+--
+-- https://www.rfc-editor.org/rfc/rfc8017#appendix-A.1.1
+
 RsaPubKey ::= SEQUENCE {
 	n INTEGER ({ rsa_get_n }),
 	e INTEGER ({ rsa_get_e })
diff --git a/fs/smb/server/ksmbd_spnego_negtokeninit.asn1 b/fs/smb/server/ksmbd_spnego_negtokeninit.asn1
index 0065f19..00151380 100644
--- a/fs/smb/server/ksmbd_spnego_negtokeninit.asn1
+++ b/fs/smb/server/ksmbd_spnego_negtokeninit.asn1
@@ -1,3 +1,11 @@
+-- SPDX-License-Identifier: BSD-3-Clause
+--
+-- Copyright (C) 1998, 2000 IETF Trust and the persons identified as authors
+-- of the code
+--
+-- https://www.rfc-editor.org/rfc/rfc2478#section-3.2.1
+-- https://www.rfc-editor.org/rfc/rfc2743#section-3.1
+
 GSSAPI ::=
 	[APPLICATION 0] IMPLICIT SEQUENCE {
 		thisMech
diff --git a/fs/smb/server/ksmbd_spnego_negtokentarg.asn1 b/fs/smb/server/ksmbd_spnego_negtokentarg.asn1
index 1151933..797e485 100644
--- a/fs/smb/server/ksmbd_spnego_negtokentarg.asn1
+++ b/fs/smb/server/ksmbd_spnego_negtokentarg.asn1
@@ -1,3 +1,10 @@
+-- SPDX-License-Identifier: BSD-3-Clause
+--
+-- Copyright (C) 1998 IETF Trust and the persons identified as authors
+-- of the code
+--
+-- https://www.rfc-editor.org/rfc/rfc2478#section-3.2.1
+
 GSSAPI ::=
 	CHOICE {
 		negTokenInit
diff --git a/net/ipv4/netfilter/nf_nat_snmp_basic.asn1 b/net/ipv4/netfilter/nf_nat_snmp_basic.asn1
index 24b7326..dc2cc57 100644
--- a/net/ipv4/netfilter/nf_nat_snmp_basic.asn1
+++ b/net/ipv4/netfilter/nf_nat_snmp_basic.asn1
@@ -1,3 +1,11 @@
+-- SPDX-License-Identifier: BSD-3-Clause
+--
+-- Copyright (C) 1990, 2002 IETF Trust and the persons identified as authors
+-- of the code
+--
+-- https://www.rfc-editor.org/rfc/rfc1157#section-4
+-- https://www.rfc-editor.org/rfc/rfc3416#section-3
+
 Message ::=
 	SEQUENCE {
 		version
