diff --git a/src/applications/legalpad/query/LegalpadDocumentQuery.php b/src/applications/legalpad/query/LegalpadDocumentQuery.php
index cca501c1eb..264bf3e018 100644
--- a/src/applications/legalpad/query/LegalpadDocumentQuery.php
+++ b/src/applications/legalpad/query/LegalpadDocumentQuery.php
@@ -9,7 +9,7 @@ final class LegalpadDocumentQuery
   private $ids;
   private $phids;
   private $creatorPHIDs;
-  private $contributorPHIDs; // TODO - T3479
+  private $contributorPHIDs;
   private $dateCreatedAfter;
   private $dateCreatedBefore;
 
@@ -62,8 +62,9 @@ final class LegalpadDocumentQuery
 
     $data = queryfx_all(
       $conn_r,
-      'SELECT legalpad_document.* FROM %T legalpad_document %Q %Q %Q',
+      'SELECT d.* FROM %T d %Q %Q %Q %Q',
       $table->getTableName(),
+      $this->buildJoinClause($conn_r),
       $this->buildWhereClause($conn_r),
       $this->buildOrderClause($conn_r),
       $this->buildLimitClause($conn_r));
@@ -89,6 +90,18 @@ final class LegalpadDocumentQuery
     return $documents;
   }
 
+  private function buildJoinClause($conn_r) {
+    $joins = array();
+
+    if ($this->contributorPHIDs) {
+      $joins[] = qsprintf(
+        $conn_r,
+        'JOIN edge e ON e.src = d.phid');
+    }
+
+    return implode(' ', $joins);
+  }
+
   protected function buildWhereClause($conn_r) {
     $where = array();
 
@@ -97,38 +110,46 @@ final class LegalpadDocumentQuery
     if ($this->ids) {
       $where[] = qsprintf(
         $conn_r,
-        'id IN (%Ld)',
+        'd.id IN (%Ld)',
         $this->ids);
     }
 
     if ($this->phids) {
       $where[] = qsprintf(
         $conn_r,
-        'phid IN (%Ls)',
+        'd.phid IN (%Ls)',
         $this->phids);
     }
 
     if ($this->creatorPHIDs) {
       $where[] = qsprintf(
         $conn_r,
-        'creatorPHID IN (%Ls)',
+        'd.creatorPHID IN (%Ls)',
         $this->creatorPHIDs);
     }
 
     if ($this->dateCreatedAfter) {
       $where[] = qsprintf(
         $conn_r,
-        'dateCreated >= %d',
+        'd.dateCreated >= %d',
         $this->dateCreatedAfter);
     }
 
     if ($this->dateCreatedBefore) {
       $where[] = qsprintf(
         $conn_r,
-        'dateCreated <= %d',
+        'd.dateCreated <= %d',
         $this->dateCreatedBefore);
     }
 
+    if ($this->contributorPHIDs) {
+      $where[] = qsprintf(
+        $conn_r,
+        'e.type = %s AND e.dst IN (%Ls)',
+        PhabricatorEdgeConfig::TYPE_OBJECT_HAS_CONTRIBUTOR,
+        $this->contributorPHIDs);
+    }
+
     return $this->formatWhereClause($where);
   }
 
diff --git a/src/applications/legalpad/query/LegalpadDocumentSearchEngine.php b/src/applications/legalpad/query/LegalpadDocumentSearchEngine.php
index 1d6a817b22..ae14b8387a 100644
--- a/src/applications/legalpad/query/LegalpadDocumentSearchEngine.php
+++ b/src/applications/legalpad/query/LegalpadDocumentSearchEngine.php
@@ -12,6 +12,10 @@ final class LegalpadDocumentSearchEngine
       'creatorPHIDs',
       array_values($request->getArr('creators')));
 
+    $saved->setParameter(
+      'contributorPHIDs',
+      array_values($request->getArr('contributors')));
+
     $saved->setParameter('createdStart', $request->getStr('createdStart'));
     $saved->setParameter('createdEnd', $request->getStr('createdEnd'));
 
@@ -22,7 +26,8 @@ final class LegalpadDocumentSearchEngine
     $query = id(new LegalpadDocumentQuery())
       ->needDocumentBodies(true)
       ->needContributors(true)
-      ->withCreatorPHIDs($saved->getParameter('creatorPHIDs', array()));
+      ->withCreatorPHIDs($saved->getParameter('creatorPHIDs', array()))
+      ->withContributorPHIDs($saved->getParameter('contributorPHIDs', array()));
 
     $start = $this->parseDateTime($saved->getParameter('createdStart'));
     $end = $this->parseDateTime($saved->getParameter('createdEnd'));
@@ -41,11 +46,15 @@ final class LegalpadDocumentSearchEngine
   public function buildSearchForm(
     AphrontFormView $form,
     PhabricatorSavedQuery $saved_query) {
-    $phids = $saved_query->getParameter('creatorPHIDs', array());
+
+    $creator_phids = $saved_query->getParameter('creatorPHIDs', array());
+    $contributor_phids = $saved_query->getParameter(
+      'contributorPHIDs', array());
+    $phids = array_merge($creator_phids, $contributor_phids);
     $handles = id(new PhabricatorObjectHandleData($phids))
       ->setViewer($this->requireViewer())
       ->loadHandles();
-    $creator_tokens = mpull($handles, 'getFullName', 'getPHID');
+    $tokens = mpull($handles, 'getFullName', 'getPHID');
 
     $form
       ->appendChild(
@@ -53,7 +62,13 @@ final class LegalpadDocumentSearchEngine
           ->setDatasource('/typeahead/common/users/')
           ->setName('creators')
           ->setLabel(pht('Creators'))
-          ->setValue($creator_tokens));
+          ->setValue(array_select_keys($tokens, $creator_phids)))
+      ->appendChild(
+        id(new AphrontFormTokenizerControl())
+          ->setDatasource('/typeahead/common/users/')
+          ->setName('contributors')
+          ->setLabel(pht('Contributors'))
+          ->setValue(array_select_keys($tokens, $contributor_phids)));
 
     $this->buildDateRange(
       $form,