diff --git a/pgpainless-core/src/main/java/org/pgpainless/util/ArmoredOutputStreamFactory.java b/pgpainless-core/src/main/java/org/pgpainless/util/ArmoredOutputStreamFactory.java
index 403115ba..67cc1c20 100644
--- a/pgpainless-core/src/main/java/org/pgpainless/util/ArmoredOutputStreamFactory.java
+++ b/pgpainless-core/src/main/java/org/pgpainless/util/ArmoredOutputStreamFactory.java
@@ -31,7 +31,11 @@ public final class ArmoredOutputStreamFactory {
      */
     public static ArmoredOutputStream get(OutputStream outputStream) {
         ArmoredOutputStream armoredOutputStream = new ArmoredOutputStream(outputStream);
-        armoredOutputStream.setHeader(ArmorUtils.HEADER_VERSION, version);
+        armoredOutputStream.clearHeaders();
+        if (version != null && !version.isEmpty()) {
+            armoredOutputStream.setHeader(ArmorUtils.HEADER_VERSION, version);
+        }
+
         for (String comment : comment) {
             ArmorUtils.addCommentHeader(armoredOutputStream, comment);
         }
@@ -55,10 +59,16 @@ public final class ArmoredOutputStreamFactory {
      * @param versionString version string
      */
     public static void setVersionInfo(String versionString) {
-        if (versionString == null || versionString.trim().isEmpty()) {
-            throw new IllegalArgumentException("Version Info MUST NOT be null NOR empty.");
+        if (versionString == null) {
+            version = null;
+            return;
+        }
+        String trimmed = versionString.trim();
+        if (trimmed.isEmpty()) {
+            version = null;
+        } else {
+            version = trimmed;
         }
-        version = versionString;
     }
 
     /**
diff --git a/pgpainless-sop/src/main/java/org/pgpainless/sop/SOPImpl.java b/pgpainless-sop/src/main/java/org/pgpainless/sop/SOPImpl.java
index 35ff8994..28772f10 100644
--- a/pgpainless-sop/src/main/java/org/pgpainless/sop/SOPImpl.java
+++ b/pgpainless-sop/src/main/java/org/pgpainless/sop/SOPImpl.java
@@ -4,6 +4,7 @@
 
 package org.pgpainless.sop;
 
+import org.pgpainless.util.ArmoredOutputStreamFactory;
 import sop.SOP;
 import sop.operation.Armor;
 import sop.operation.Dearmor;
@@ -20,6 +21,10 @@ import sop.operation.Version;
 
 public class SOPImpl implements SOP {
 
+    static {
+        ArmoredOutputStreamFactory.setVersionInfo(null);
+    }
+
     @Override
     public Version version() {
         return new VersionImpl();
diff --git a/pgpainless-sop/src/test/java/org/pgpainless/sop/ExtractCertTest.java b/pgpainless-sop/src/test/java/org/pgpainless/sop/ExtractCertTest.java
index 84a1f471..b3910482 100644
--- a/pgpainless-sop/src/test/java/org/pgpainless/sop/ExtractCertTest.java
+++ b/pgpainless-sop/src/test/java/org/pgpainless/sop/ExtractCertTest.java
@@ -18,7 +18,6 @@ import sop.exception.SOPGPException;
 public class ExtractCertTest {
 
     public static final String key = "-----BEGIN PGP PRIVATE KEY BLOCK-----\n" +
-            "Version: PGPainless\n" +
             "Comment: A8D9 9FF4 C8DD BBA6 C610  A6B7 9ACB 2195 A9BC DF5B\n" +
             "Comment: Alice <alice@pgpainless.org>\n" +
             "\n" +
@@ -42,7 +41,6 @@ public class ExtractCertTest {
             "-----END PGP PRIVATE KEY BLOCK-----\n";
 
     public static final String cert = "-----BEGIN PGP PUBLIC KEY BLOCK-----\n" +
-            "Version: PGPainless\n" +
             "Comment: A8D9 9FF4 C8DD BBA6 C610  A6B7 9ACB 2195 A9BC DF5B\n" +
             "Comment: Alice <alice@pgpainless.org>\n" +
             "\n" +