diff --git a/src/main-conf.c b/src/main-conf.c
index e1394375..cc5bf945 100644
--- a/src/main-conf.c
+++ b/src/main-conf.c
@@ -1247,6 +1247,7 @@ static int SET_output_format(struct Masscan *masscan, const char *name, const ch
             case Output_NDJSON:     fprintf(fp, "output-format = ndjson\n"); break;
             case Output_Certs:      fprintf(fp, "output-format = certs\n"); break;
             case Output_None:       fprintf(fp, "output-format = none\n"); break;
+            case Output_Hostonly:   fprintf(fp, "output-format = hostonly\n"); break;
             case Output_Redis:
                 fprintf(fp, "output-format = redis\n");
                 fprintf(fp, "redis = %s %u\n",
@@ -1273,6 +1274,7 @@ static int SET_output_format(struct Masscan *masscan, const char *name, const ch
     else if (EQUALS("certs", value))        x = Output_Certs;
     else if (EQUALS("none", value))         x = Output_None;
     else if (EQUALS("redis", value))        x = Output_Redis;
+    else if (EQUALS("hostonly", value))     x = Output_Hostonly;
     else {
         LOG(0, "FAIL: unknown output-format: %s\n", value);
         LOG(0, "  hint: 'binary', 'xml', 'grepable', ...\n");
@@ -2686,6 +2688,9 @@ masscan_command_line(struct Masscan *masscan, int argc, char *argv[])
                 case 'U':
                     masscan_set_parameter(masscan, "output-format", "unicornscan");
                     break;
+                case 'H':
+                    masscan_set_parameter(masscan, "output-format", "hostonly");
+                    break;
                 default:
                     fprintf(stderr, "nmap(%s): unknown output format\n", argv[i]);
                     exit(1);
@@ -2864,7 +2869,7 @@ masscan_command_line(struct Masscan *masscan, int argc, char *argv[])
         fprintf(stderr, "[-] WARNING: the shard number must be less than the total shard count: %u/%u\n",
             masscan->shard.one, masscan->shard.of);
     }
-    if (masscan->shard.of && masscan->seed == 0) {
+    if (masscan->shard.of > 1 && masscan->seed == 0) {
         fprintf(stderr, "[-] WARNING: --seed <num> is not specified\n    HINT: all shards must share the same seed\n");
     }
 }
diff --git a/src/masscan.h b/src/masscan.h
index a78ab567..58a0478e 100644
--- a/src/masscan.h
+++ b/src/masscan.h
@@ -58,6 +58,7 @@ enum OutputFormat {
     Output_Unicornscan  = 0x0200,   /* -oU, "unicornscan" */
     Output_None         = 0x0400,
     Output_Certs        = 0x0800,
+    Output_Hostonly     = 0x1000,   /* -oH, "hostonly" */
     Output_All          = 0xFFBF,   /* not supported */
 };
 
diff --git a/src/output.c b/src/output.c
index 44bc8157..c15a7bbe 100644
--- a/src/output.c
+++ b/src/output.c
@@ -441,6 +441,9 @@ output_create(const struct Masscan *masscan, unsigned thread_index)
     case Output_Redis:
         out->funcs = &redis_output;
         break;
+    case Output_Hostonly:
+        out->funcs = &hostonly_output;
+        break;
     case Output_None:
         out->funcs = &null_output;
         break;
diff --git a/src/output.h b/src/output.h
index 34e591de..41682014 100644
--- a/src/output.h
+++ b/src/output.h
@@ -141,6 +141,7 @@ extern const struct OutputType certs_output;
 extern const struct OutputType binary_output;
 extern const struct OutputType null_output;
 extern const struct OutputType redis_output;
+extern const struct OutputType hostonly_output;
 extern const struct OutputType grepable_output;
 
 /**
diff --git a/vs10/masscan.vcxproj b/vs10/masscan.vcxproj
index dda27bf2..a64cce14 100644
--- a/vs10/masscan.vcxproj
+++ b/vs10/masscan.vcxproj
@@ -38,6 +38,7 @@
     <ClCompile Include="..\src\out-binary.c" />
     <ClCompile Include="..\src\out-certs.c" />
     <ClCompile Include="..\src\out-grepable.c" />
+    <ClCompile Include="..\src\out-hostonly.c" />
     <ClCompile Include="..\src\out-json.c" />
     <ClCompile Include="..\src\out-ndjson.c" />
     <ClCompile Include="..\src\out-null.c" />
diff --git a/vs10/masscan.vcxproj.filters b/vs10/masscan.vcxproj.filters
index 951778f5..ac4d71a2 100644
--- a/vs10/masscan.vcxproj.filters
+++ b/vs10/masscan.vcxproj.filters
@@ -375,6 +375,9 @@
     <ClCompile Include="..\src\massip-addr.c">
       <Filter>Source Files\massip</Filter>
     </ClCompile>
+    <ClCompile Include="..\src\out-hostonly.c">
+      <Filter>Source Files\output</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="..\src\proto-arp.h">