diff --git a/src/applications/phortune/controller/merchant/PhortuneMerchantInvoiceCreateController.php b/src/applications/phortune/controller/merchant/PhortuneMerchantInvoiceCreateController.php
--- a/src/applications/phortune/controller/merchant/PhortuneMerchantInvoiceCreateController.php
+++ b/src/applications/phortune/controller/merchant/PhortuneMerchantInvoiceCreateController.php
@@ -58,9 +58,10 @@
     }
 
     if (!$target_account) {
-      $accounts = PhortuneAccountQuery::loadAccountsForUser(
-        $target_user,
-        PhabricatorContentSource::newFromRequest($request));
+      $accounts = id(new PhortuneAccountQuery())
+        ->setViewer($viewer)
+        ->withMemberPHIDs(array($target_user->getPHID()))
+        ->execute();
 
       $form = id(new AphrontFormView())
         ->setUser($viewer)
diff --git a/src/applications/phortune/query/PhortuneMerchantQuery.php b/src/applications/phortune/query/PhortuneMerchantQuery.php
--- a/src/applications/phortune/query/PhortuneMerchantQuery.php
+++ b/src/applications/phortune/query/PhortuneMerchantQuery.php
@@ -86,14 +86,14 @@
     if ($this->ids !== null) {
       $where[] = qsprintf(
         $conn,
-        'id IN (%Ld)',
+        'merchant.id IN (%Ld)',
         $this->ids);
     }
 
     if ($this->phids !== null) {
       $where[] = qsprintf(
         $conn,
-        'phid IN (%Ls)',
+        'merchant.phid IN (%Ls)',
         $this->phids);
     }
 
@@ -113,7 +113,7 @@
     if ($this->memberPHIDs !== null) {
       $joins[] = qsprintf(
         $conn,
-        'LEFT JOIN %T e ON m.phid = e.src AND e.type = %d',
+        'LEFT JOIN %T e ON merchant.phid = e.src AND e.type = %d',
         PhabricatorEdgeConfig::TABLE_NAME_EDGE,
         PhortuneMerchantHasMemberEdgeType::EDGECONST);
     }
@@ -126,7 +126,68 @@
   }
 
   protected function getPrimaryTableAlias() {
-    return 'm';
+    return 'merchant';
+  }
+
+  public static function canViewersEditMerchants(
+    array $viewer_phids,
+    array $merchant_phids) {
+
+    // See T13366 for some discussion. This is an unusual caching construct to
+    // make policy filtering of Accounts easier.
+
+    foreach ($viewer_phids as $key => $viewer_phid) {
+      if (!$viewer_phid) {
+        unset($viewer_phids[$key]);
+      }
+    }
+
+    if (!$viewer_phids) {
+      return array();
+    }
+
+    $cache_key = 'phortune.merchant.can-edit';
+    $cache = PhabricatorCaches::getRequestCache();
+
+    $cache_data = $cache->getKey($cache_key);
+    if (!$cache_data) {
+      $cache_data = array();
+    }
+
+    $load_phids = array();
+    foreach ($viewer_phids as $viewer_phid) {
+      if (!isset($cache_data[$viewer_phid])) {
+        $load_phids[] = $viewer_phid;
+      }
+    }
+
+    $did_write = false;
+    foreach ($load_phids as $load_phid) {
+      $merchants = id(new self())
+        ->setViewer(PhabricatorUser::getOmnipotentUser())
+        ->withMemberPHIDs(array($load_phid))
+        ->execute();
+      foreach ($merchants as $merchant) {
+        $cache_data[$load_phid][$merchant->getPHID()] = true;
+        $did_write = true;
+      }
+    }
+
+    if ($did_write) {
+      $cache->setKey($cache_key, $cache_data);
+    }
+
+    $results = array();
+    foreach ($viewer_phids as $viewer_phid) {
+      foreach ($merchant_phids as $merchant_phid) {
+        if (!isset($cache_data[$viewer_phid][$merchant_phid])) {
+          continue;
+        }
+        $results[$viewer_phid][$merchant_phid] = true;
+      }
+    }
+
+    return $results;
   }
 
 }
diff --git a/src/applications/phortune/storage/PhortuneAccount.php b/src/applications/phortune/storage/PhortuneAccount.php
--- a/src/applications/phortune/storage/PhortuneAccount.php
+++ b/src/applications/phortune/storage/PhortuneAccount.php
@@ -179,13 +179,18 @@
       return true;
     }
 
-    // If the viewer is acting on behalf of a merchant, they can see
-    // payment accounts.
+    // See T13366. If the viewer can edit any merchant that this payment
+    // account has a relationship with, they can see the payment account.
     if ($capability == PhabricatorPolicyCapability::CAN_VIEW) {
-      foreach ($viewer->getAuthorities() as $authority) {
-        if ($authority instanceof PhortuneMerchant) {
-          return true;
-        }
+      $viewer_phids = array($viewer->getPHID());
+      $merchant_phids = $this->getMerchantPHIDs();
+
+      $any_edit = PhortuneMerchantQuery::canViewersEditMerchants(
+        $viewer_phids,
+        $merchant_phids);
+
+      if ($any_edit) {
+        return true;
       }
     }
 
@@ -193,7 +198,10 @@
   }
 
   public function describeAutomaticCapability($capability) {
-    return pht('Members of an account can always view and edit it.');
+    return array(
+      pht('Members of an account can always view and edit it.'),
+      pht('Merchants an account has established a relationship can view it.'),
+    );
   }