diff --git a/app/logical/post_query_builder.rb b/app/logical/post_query_builder.rb
index cb2ec7a0a..9eaf29a6a 100644
--- a/app/logical/post_query_builder.rb
+++ b/app/logical/post_query_builder.rb
@@ -170,6 +170,20 @@ class PostQueryBuilder
       end
     end
 
+    if q[:source_neg]
+      if q[:source_neg] == "none%"
+        relation = relation.where("(posts.source != '' AND posts.source IS NOT NULL)")
+      elsif q[:source_neg] == "http%"
+        relation = relation.where("(posts.source not like ?)", "http%")
+      elsif q[:source_neg] =~ /^%\.?pixiv(?:\.net(?:\/img)?)?(?:%\/|(?=%$))(.+)$/
+        relation = relation.where("SourcePattern(posts.source) NOT LIKE ? ESCAPE E'\\\\'", "pixiv/" + $1)
+        has_constraints!
+      else
+        relation = relation.where("SourcePattern(posts.source) NOT LIKE SourcePattern(?) ESCAPE E'\\\\'", q[:source_neg])
+        has_constraints!
+      end
+    end
+
     if q[:subscriptions]
       relation = add_tag_subscription_relation(q[:subscriptions], relation)
       has_constraints!
diff --git a/app/models/tag.rb b/app/models/tag.rb
index 71c570c85..e692922ca 100644
--- a/app/models/tag.rb
+++ b/app/models/tag.rb
@@ -1,5 +1,5 @@
 class Tag < ActiveRecord::Base
-  METATAGS = "-user|user|-approver|approver|commenter|comm|noter|-pool|pool|-fav|fav|sub|md5|-rating|rating|-locked|locked|width|height|mpixels|score|favcount|filesize|source|id|-id|date|age|order|-status|status|tagcount|gentags|arttags|chartags|copytags|parent|-parent|pixiv_id|pixiv"
+  METATAGS = "-user|user|-approver|approver|commenter|comm|noter|-pool|pool|-fav|fav|sub|md5|-rating|rating|-locked|locked|width|height|mpixels|score|favcount|filesize|source|-source|id|-id|date|age|order|-status|status|tagcount|gentags|arttags|chartags|copytags|parent|-parent|pixiv_id|pixiv"
   attr_accessible :category
   has_one :wiki_page, :foreign_key => "name", :primary_key => "title"
 
@@ -399,6 +399,9 @@ class Tag < ActiveRecord::Base
           when "source"
             q[:source] = ($2.to_escaped_for_sql_like + "%").gsub(/%+/, '%')
 
+          when "-source"
+            q[:source_neg] = ($2.to_escaped_for_sql_like + "%").gsub(/%+/, '%')
+
           when "date"
             q[:date] = parse_helper($2, :date)