diff --git a/source/tools/detect/irqoff/bpf/irqoff.bpf.c b/source/tools/detect/irqoff/bpf/irqoff.bpf.c
index 19f4b16c3e6518869620c4cf0d5ba4240206bebb..849fbdaccdc1ed6cd5826b0bfadcddc5975e9ac4 100644
--- a/source/tools/detect/irqoff/bpf/irqoff.bpf.c
+++ b/source/tools/detect/irqoff/bpf/irqoff.bpf.c
@@ -1,4 +1,3 @@
-// SPDX-License-Identifier: GPL-2.0
 #include <vmlinux.h>
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_tracing.h>
diff --git a/source/tools/detect/irqoff/irqoff.c b/source/tools/detect/irqoff/irqoff.c
index aeb802ddef400ebe3d7572b17c694249962ac268..d81658709bab9c23693f995695687f8824f5cba9 100644
--- a/source/tools/detect/irqoff/irqoff.c
+++ b/source/tools/detect/irqoff/irqoff.c
@@ -1,5 +1,3 @@
-// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
-
 #include <argp.h>
 #include <signal.h>
 #include <stdio.h>
diff --git a/source/tools/detect/irqoff/irqoff.h b/source/tools/detect/irqoff/irqoff.h
index 164e2825b1c8caeaa12c8787efff7e5bda8be29e..98682d02abcf09686b003d12c785874809879637 100644
--- a/source/tools/detect/irqoff/irqoff.h
+++ b/source/tools/detect/irqoff/irqoff.h
@@ -1,4 +1,3 @@
-/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
 #ifndef __IRQOFF_H
 #define __IRQOFF_H
 
diff --git a/source/tools/detect/net_diag/rtrace/ebpf/utils/disasm.c b/source/tools/detect/net_diag/rtrace/ebpf/utils/disasm.c
index 130ff88078f7eaec2871cbe378152258313328f3..78cfe363bbdef910990fdc5aecb73de4f2d115c2 100644
--- a/source/tools/detect/net_diag/rtrace/ebpf/utils/disasm.c
+++ b/source/tools/detect/net_diag/rtrace/ebpf/utils/disasm.c
@@ -1,8 +1,3 @@
-// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
-/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
- * Copyright (c) 2016 Facebook
- */
-
 #include <linux/bpf.h>
 #include <stdarg.h>
 #include <stdio.h>
diff --git a/source/tools/detect/syscall_slow/bpf/syscall_slow.bpf.c b/source/tools/detect/syscall_slow/bpf/syscall_slow.bpf.c
index 9290e2568f507de7823c7c5e91468e48f7864703..40e656e381f4b3e1dd72b3b5ebe5317f2aef48b6 100644
--- a/source/tools/detect/syscall_slow/bpf/syscall_slow.bpf.c
+++ b/source/tools/detect/syscall_slow/bpf/syscall_slow.bpf.c
@@ -1,4 +1,3 @@
-// SPDX-License-Identifier: GPL-2.0
 #include <vmlinux.h>
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_core_read.h>
diff --git a/source/tools/detect/syscall_slow/syscall_slow.c b/source/tools/detect/syscall_slow/syscall_slow.c
index 8a0e6df07414afd4de139f811bde17db903af801..bf50fa2f81db3c8950d9fa5f5015fd66cec7dbeb 100644
--- a/source/tools/detect/syscall_slow/syscall_slow.c
+++ b/source/tools/detect/syscall_slow/syscall_slow.c
@@ -1,5 +1,3 @@
-// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
-
 #include <argp.h>
 #include <signal.h>
 #include <stdio.h>
diff --git a/source/tools/detect/syscall_slow/syscall_slow.h b/source/tools/detect/syscall_slow/syscall_slow.h
index 2cccc05488191a7c977ac91e95b08eb439c07fb5..7ef3602f7c7e76e5266b222ab36e1dd1f3432143 100644
--- a/source/tools/detect/syscall_slow/syscall_slow.h
+++ b/source/tools/detect/syscall_slow/syscall_slow.h
@@ -1,4 +1,3 @@
-/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
 #ifndef __IRQOFF_H
 #define __IRQOFF_H
 
diff --git a/source/tools/monitor/sched/nosched/bpf/nosched.bpf.c b/source/tools/monitor/sched/nosched/bpf/nosched.bpf.c
index b879a6d2ee0b477f559b98b923792d62b1ea3c82..d0a14624c27851d83529fb2a8b2a62fd1d0b40d6 100644
--- a/source/tools/monitor/sched/nosched/bpf/nosched.bpf.c
+++ b/source/tools/monitor/sched/nosched/bpf/nosched.bpf.c
@@ -1,10 +1,3 @@
-// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
-/* Copyright (c) 2021 Sartura */
-/*
- * Todo: 1. how to distinguish CONFIG_THREAD_INFO_IN_TASK configured?
- *       2. why #ifdef __x86_64__ not work at nosched.bpf.c?
- *       3. some magic NUMBER, like max_entries, need to be configable
- * */
 #include <vmlinux.h>
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_tracing.h>
diff --git a/source/tools/monitor/sched/nosched/nosched.c b/source/tools/monitor/sched/nosched/nosched.c
index c087970a9aa97f745a3ce3b0b4534f5f58e45e15..32c13af095e3b852fdef13fa193607673f30fbe8 100644
--- a/source/tools/monitor/sched/nosched/nosched.c
+++ b/source/tools/monitor/sched/nosched/nosched.c
@@ -1,7 +1,3 @@
-// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
-/* Copyright (c) 2021 Sartura
- * Based on minimal.c by Facebook */
-
 #include <stdio.h>
 #include <unistd.h>
 #include <stdlib.h>
diff --git a/source/tools/monitor/sched/runqslower/bpf/runqslower.bpf.c b/source/tools/monitor/sched/runqslower/bpf/runqslower.bpf.c
index d362fd3fc283a98628869699172dca105fce38c8..6eb8b2687955cc3deefb0facb6b6ffce062bfb03 100644
--- a/source/tools/monitor/sched/runqslower/bpf/runqslower.bpf.c
+++ b/source/tools/monitor/sched/runqslower/bpf/runqslower.bpf.c
@@ -1,5 +1,3 @@
-// SPDX-License-Identifier: GPL-2.0
-// Copyright (c) 2019 Facebook
 #include <vmlinux.h>
 #include <bpf/bpf_helpers.h>
 #include "../runqslower.h"
diff --git a/source/tools/monitor/sched/runqslower/runqslower.c b/source/tools/monitor/sched/runqslower/runqslower.c
index 0b948182c12ac0775ba4d2446404289d36d7b07e..6e2ccfb178c5d1a162e01f8eb41447ce3a07c3c5 100644
--- a/source/tools/monitor/sched/runqslower/runqslower.c
+++ b/source/tools/monitor/sched/runqslower/runqslower.c
@@ -1,8 +1,3 @@
-// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
-// Copyright (c) 2019 Facebook
-//
-// Based on runqslower(8) from BCC by Ivan Babrou.
-// 11-Feb-2020   Andrii Nakryiko   Created this.
 #include <argp.h>
 #include <unistd.h>
 #include <signal.h>
@@ -40,8 +35,6 @@ struct env {
 };
 
 const char *argp_program_version = "runqslower 0.1";
-const char *argp_program_bug_address =
-	"https://github.com/iovisor/bcc/tree/master/libbpf-tools";
 const char argp_program_doc[] =
 "Trace high run queue latency.\n"
 "\n"
diff --git a/source/tools/monitor/sched/runqslower/runqslower.h b/source/tools/monitor/sched/runqslower/runqslower.h
index 8f9253a03efa68e51c0b5b1ae14a7c3bc935d1b2..31dfc8f6a8c46343ed08d9b9e454ce843f5170dd 100644
--- a/source/tools/monitor/sched/runqslower/runqslower.h
+++ b/source/tools/monitor/sched/runqslower/runqslower.h
@@ -1,4 +1,3 @@
-/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
 #ifndef __RUNQSLOWER_H
 #define __RUNQSLOWER_H
 
diff --git a/source/tools/monitor/sched/schedmoni/bpf/schedmoni.bpf.c b/source/tools/monitor/sched/schedmoni/bpf/schedmoni.bpf.c
index 4c29af8ebf84589a817bb187953f0e39f58ad1b1..4f1428bb841b04380243153c0f7b7563dceca0d6 100644
--- a/source/tools/monitor/sched/schedmoni/bpf/schedmoni.bpf.c
+++ b/source/tools/monitor/sched/schedmoni/bpf/schedmoni.bpf.c
@@ -1,4 +1,3 @@
-// SPDX-License-Identifier: GPL-2.0
 #include <vmlinux.h>
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_tracing.h>
diff --git a/source/tools/monitor/sched/schedmoni/nosched.c b/source/tools/monitor/sched/schedmoni/nosched.c
index b7d8f56983ff68efa8d8d73a748e494aa78e36f2..36a86118ea9b223818a2b2a7290ce65ca0c3d57e 100644
--- a/source/tools/monitor/sched/schedmoni/nosched.c
+++ b/source/tools/monitor/sched/schedmoni/nosched.c
@@ -1,7 +1,3 @@
-// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
-/* Copyright (c) 2021 Sartura
- * Based on minimal.c by Facebook */
-
 #include <stdio.h>
 #include <unistd.h>
 #include <stdlib.h>
diff --git a/source/tools/monitor/sched/schedmoni/schedmoni.c b/source/tools/monitor/sched/schedmoni/schedmoni.c
index fe0bda817650e238c1562320a587e7223e721c97..e36444e8dfc5aeb3d618c98e3390e68db0b0519a 100644
--- a/source/tools/monitor/sched/schedmoni/schedmoni.c
+++ b/source/tools/monitor/sched/schedmoni/schedmoni.c
@@ -1,4 +1,3 @@
-// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
 #include <argp.h>
 #include <unistd.h>
 #include <signal.h>
diff --git a/source/tools/monitor/sched/schedmoni/schedmoni.h b/source/tools/monitor/sched/schedmoni/schedmoni.h
index f7f4e651665a387276260af684cab3a428905d9f..282eae63207a64b0a54f9fba8412244ab4532091 100644
--- a/source/tools/monitor/sched/schedmoni/schedmoni.h
+++ b/source/tools/monitor/sched/schedmoni/schedmoni.h
@@ -1,4 +1,3 @@
-/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
 #ifndef __RUNQSLOWER_H
 #define __RUNQSLOWER_H
 #define TASK_COMM_LEN 16