diff --git a/src/IP.ts b/src/IP.ts
index 3e1b87f..910b8c3 100644
--- a/src/IP.ts
+++ b/src/IP.ts
@@ -1,4 +1,4 @@
-/*
+/*!
  * Copyright © 2025 Cloudnode OÜ.
  *
  * This file is part of @cldn/ip.
diff --git a/src/IPAddress.ts b/src/IPAddress.ts
index fa59998..1d546c6 100644
--- a/src/IPAddress.ts
+++ b/src/IPAddress.ts
@@ -1,4 +1,4 @@
-/*
+/*!
  * Copyright © 2024–2025 Cloudnode OÜ.
  *
  * This file is part of @cldn/ip.
diff --git a/src/IPv4.ts b/src/IPv4.ts
index 68e3bfa..7666b2f 100644
--- a/src/IPv4.ts
+++ b/src/IPv4.ts
@@ -1,4 +1,4 @@
-/*
+/*!
  * Copyright © 2024–2025 Cloudnode OÜ.
  *
  * This file is part of @cldn/ip.
diff --git a/src/IPv6.ts b/src/IPv6.ts
index 81e4363..8d7ef13 100644
--- a/src/IPv6.ts
+++ b/src/IPv6.ts
@@ -1,4 +1,4 @@
-/*
+/*!
  * Copyright © 2024–2025 Cloudnode OÜ.
  *
  * This file is part of @cldn/ip.
diff --git a/src/Network.ts b/src/Network.ts
index ab606ae..c9397be 100644
--- a/src/Network.ts
+++ b/src/Network.ts
@@ -1,4 +1,4 @@
-/*
+/*!
  * Copyright © 2025 Cloudnode OÜ.
  *
  * This file is part of @cldn/ip.
diff --git a/src/Subnet.ts b/src/Subnet.ts
index 67ebc59..b8da753 100644
--- a/src/Subnet.ts
+++ b/src/Subnet.ts
@@ -1,4 +1,4 @@
-/*
+/*!
  * Copyright © 2024–2025 Cloudnode OÜ.
  *
  * This file is part of @cldn/ip.
diff --git a/src/SubnetList.ts b/src/SubnetList.ts
index c6bf622..85452e8 100644
--- a/src/SubnetList.ts
+++ b/src/SubnetList.ts
@@ -1,4 +1,4 @@
-/*
+/*!
  * Copyright © 2024–2025 Cloudnode OÜ.
  *
  * This file is part of @cldn/ip.
diff --git a/src/index.ts b/src/index.ts
index 7d67d68..a89fb6d 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,4 +1,4 @@
-/*
+/*!
  * Copyright © 2024 Cloudnode OÜ.
  *
  * This file is part of @cldn/ip.
@@ -14,6 +14,7 @@
  * You should have received a copy of the GNU Lesser General Public License along with @cldn/ip.
  * If not, see <https://www.gnu.org/licenses/>.
  */
+
 export {IP} from "./IP.js";
 export {IPAddress} from "./IPAddress.js";
 export {IPv4} from "./IPv4.js";