diff --git a/Classes/PHPExcel/Reader/Excel5.php b/Classes/PHPExcel/Reader/Excel5.php
index d264774..4dba020 100644
--- a/Classes/PHPExcel/Reader/Excel5.php
+++ b/Classes/PHPExcel/Reader/Excel5.php
@@ -3898,8 +3898,9 @@ class PHPExcel_Reader_Excel5 implements PHPExcel_Reader_IReader
 		if (!is_null($this->getReadFilter())) {
 			$includeCellRange = false;
 			$rangeBoundaries = PHPExcel_Cell::getRangeBoundaries($cellRangeAddress);
+			$rangeBoundaries[1][0]++;
 			for ($row = $rangeBoundaries[0][1]; $row <= $rangeBoundaries[1][1]; $row++) {
-				for ($column = $rangeBoundaries[0][0]; $column <= $rangeBoundaries[1][0]; $column++) {
+				for ($column = $rangeBoundaries[0][0]; $column != $rangeBoundaries[1][0]; $column++) {
 					if ($this->getReadFilter()->readCell($column, $row, $this->_phpSheet->getTitle())) {
 						$includeCellRange = true;
 						break 2;
diff --git a/changelog.txt b/changelog.txt
index 1655ec6..fb3cfc8 100644
--- a/changelog.txt
+++ b/changelog.txt
@@ -44,6 +44,7 @@ Fixed in SVN:
 - Bugfix:	(MBaker) Work item 13374 - file that makes cells go black
 - Bugfix:	(MBaker) Minor patchfix for Excel2003XML Reader when XML is defined with a charset attribute
 - Bugfix:	(MBaker) Work item 15089 - PHPExcel_Worksheet->toArray() index problem
+- Bugfix:	(MBaker) Work item 15094 - Merge cells 'un-merge' when using an existing spreadsheet
 - General:  (MBaker) Improved performance (speed), for building the Shared Strings table in the Excel2007 Writer.