diff --git a/lib/private/Files/Cache/Cache.php b/lib/private/Files/Cache/Cache.php
index 7b42cc2aa5..ef1f0f3c87 100644
--- a/lib/private/Files/Cache/Cache.php
+++ b/lib/private/Files/Cache/Cache.php
@@ -3,6 +3,7 @@
  * @copyright Copyright (c) 2016, ownCloud, Inc.
  *
  * @author Andreas Fischer <bantu@owncloud.com>
+ * @author Ari Selseng <ari@selseng.net>
  * @author Artem Kochnev <MrJeos@gmail.com>
  * @author Björn Schießle <bjoern@schiessle.org>
  * @author Florin Peter <github@florin-peter.de>
@@ -774,17 +775,40 @@ class Cache implements ICache {
 	 * @param string|boolean $path
 	 * @param array $data (optional) meta data of the folder
 	 */
-	public function correctFolderSize($path, $data = null) {
+	public function correctFolderSize($path, $data = null, $isBackgroundScan = false) {
 		$this->calculateFolderSize($path, $data);
 		if ($path !== '') {
 			$parent = dirname($path);
 			if ($parent === '.' or $parent === '/') {
 				$parent = '';
 			}
-			$this->correctFolderSize($parent);
+			if ($isBackgroundScan) {
+				$parentData = $this->get($parent);
+				if ($parentData['size'] !== -1 && $this->getIncompleteChildrenCount($parentData['fileid']) === 0) {
+					$this->correctFolderSize($parent, $parentData, $isBackgroundScan);
+				}
+			} else {
+				$this->correctFolderSize($parent);
+			}
 		}
 	}
 
+	/**
+	 * get the incomplete count that shares parent $folder
+	 *
+	 * @param int $fileId the file id of the folder
+	 * @return int
+	 */
+	public function getIncompleteChildrenCount($fileId) {
+		if ($fileId > -1) {
+			$sql = 'SELECT count(*)
+					FROM `*PREFIX*filecache` WHERE `parent` = ? AND size = -1';
+			$result = $this->connection->executeQuery($sql, [$fileId]);
+			return (int)$result->fetchColumn();
+		}
+		return -1;
+	}
+
 	/**
 	 * calculate the size of a folder and set it in the cache
 	 *
@@ -919,4 +943,4 @@ class Cache implements ICache {
 
 		return trim(\OC_Util::normalizeUnicode($path), '/');
 	}
-}
+}
\ No newline at end of file
diff --git a/lib/private/Files/Cache/Scanner.php b/lib/private/Files/Cache/Scanner.php
index ca9a0b794f..e684b85310 100644
--- a/lib/private/Files/Cache/Scanner.php
+++ b/lib/private/Files/Cache/Scanner.php
@@ -532,7 +532,7 @@ class Scanner extends BasicEmitter implements IScanner {
 			$callback();
 			\OC_Hook::emit('Scanner', 'correctFolderSize', array('path' => $path));
 			if ($this->cacheActive && $this->cache instanceof Cache) {
-				$this->cache->correctFolderSize($path);
+				$this->cache->correctFolderSize($path, null, true);
 			}
 		} catch (\OCP\Files\StorageInvalidException $e) {
 			// skip unavailable storages
diff --git a/lib/private/Files/Cache/Wrapper/CacheJail.php b/lib/private/Files/Cache/Wrapper/CacheJail.php
index 57f58e7d83..7e113d1367 100644
--- a/lib/private/Files/Cache/Wrapper/CacheJail.php
+++ b/lib/private/Files/Cache/Wrapper/CacheJail.php
@@ -265,9 +265,9 @@ class CacheJail extends CacheWrapper {
 	 * @param string|boolean $path
 	 * @param array $data (optional) meta data of the folder
 	 */
-	public function correctFolderSize($path, $data = null) {
+	public function correctFolderSize($path, $data = null, $isBackgroundSize = false) {
 		if ($this->getCache() instanceof Cache) {
-			$this->getCache()->correctFolderSize($this->getSourcePath($path), $data);
+			$this->getCache()->correctFolderSize($this->getSourcePath($path), $data, $isBackgroundSize);
 		}
 	}
 
diff --git a/lib/private/Files/Cache/Wrapper/CacheWrapper.php b/lib/private/Files/Cache/Wrapper/CacheWrapper.php
index da0a1b54e7..223e678f32 100644
--- a/lib/private/Files/Cache/Wrapper/CacheWrapper.php
+++ b/lib/private/Files/Cache/Wrapper/CacheWrapper.php
@@ -258,9 +258,9 @@ class CacheWrapper extends Cache {
 	 * @param string|boolean $path
 	 * @param array $data (optional) meta data of the folder
 	 */
-	public function correctFolderSize($path, $data = null) {
+	public function correctFolderSize($path, $data = null, $isBackgroundScan = false) {
 		if ($this->getCache() instanceof Cache) {
-			$this->getCache()->correctFolderSize($path, $data);
+			$this->getCache()->correctFolderSize($path, $data, $isBackgroundScan);
 		}
 	}
 
diff --git a/tests/lib/Files/Cache/ScannerTest.php b/tests/lib/Files/Cache/ScannerTest.php
index 736df2174d..0f5335f441 100644
--- a/tests/lib/Files/Cache/ScannerTest.php
+++ b/tests/lib/Files/Cache/ScannerTest.php
@@ -203,6 +203,44 @@ class ScannerTest extends \Test\TestCase {
 		$this->assertFalse($this->cache->getIncomplete());
 	}
 
+	public function testBackgroundScanNestedIncompleteFolders() {
+		$this->storage->mkdir('folder');
+		$this->scanner->backgroundScan();
+		
+		$this->storage->mkdir('folder/subfolder1');
+		$this->storage->mkdir('folder/subfolder2');
+		
+		$this->storage->mkdir('folder/subfolder1/subfolder3');
+		$this->cache->put('folder', ['size' => -1]);
+		$this->cache->put('folder/subfolder1', ['size' => -1]);
+		
+		// do a scan to get the folders into the cache.
+		$this->scanner->backgroundScan();
+
+		$this->assertTrue($this->cache->inCache('folder/subfolder1/subfolder3'));
+		
+		$this->storage->file_put_contents('folder/subfolder1/bar1.txt', 'foobar');
+		$this->storage->file_put_contents('folder/subfolder1/subfolder3/bar3.txt', 'foobar');
+		$this->storage->file_put_contents('folder/subfolder2/bar2.txt', 'foobar');
+
+		//mark folders as incomplete.
+		$this->cache->put('folder/subfolder1', ['size' => -1]);
+		$this->cache->put('folder/subfolder2', ['size' => -1]);
+		$this->cache->put('folder/subfolder1/subfolder3', ['size' => -1]);
+		
+		$this->scanner->backgroundScan();
+
+		$this->assertTrue($this->cache->inCache('folder/subfolder1/bar1.txt'));
+		$this->assertTrue($this->cache->inCache('folder/subfolder2/bar2.txt'));
+		$this->assertTrue($this->cache->inCache('folder/subfolder1/subfolder3/bar3.txt'));
+
+		//check if folder sizes are correct.
+		$this->assertEquals(18, $this->cache->get('folder')['size']);
+		$this->assertEquals(12, $this->cache->get('folder/subfolder1')['size']);
+		$this->assertEquals(6, $this->cache->get('folder/subfolder1/subfolder3')['size']);
+		$this->assertEquals(6, $this->cache->get('folder/subfolder2')['size']);
+	}
+
 	public function testReuseExisting() {
 		$this->fillTestFolders();