diff --git a/src/Data/QRMatrix.php b/src/Data/QRMatrix.php
index 89cb4d69d..f2761391d 100755
--- a/src/Data/QRMatrix.php
+++ b/src/Data/QRMatrix.php
@@ -582,6 +582,7 @@ final class QRMatrix{
 	 * Please test thoroughly before using this feature in production.
 	 *
 	 * This method should be called from within an output module (after the matrix has been filled with data).
+	 * Note that there is no restiction on how many times this method could be called on the same matrix instance.
 	 *
 	 * @link https://github.com/chillerlan/php-qrcode/issues/52
 	 *
diff --git a/tests/Data/QRMatrixTest.php b/tests/Data/QRMatrixTest.php
index 7e3cb6e73..68b31a5de 100755
--- a/tests/Data/QRMatrixTest.php
+++ b/tests/Data/QRMatrixTest.php
@@ -13,6 +13,7 @@
 namespace chillerlan\QRCodeTest\Data;
 
 use chillerlan\QRCode\QRCode;
+use chillerlan\QRCode\QROptions;
 use chillerlan\QRCode\Data\{QRCodeDataException, QRMatrix};
 use PHPUnit\Framework\TestCase;
 use ReflectionClass;
@@ -178,6 +179,8 @@ final class QRMatrixTest extends TestCase{
 
 		if($version === 1){
 			$this->markTestSkipped('N/A');
+
+			/** @noinspection PhpUnreachableStatementInspection */
 			return;
 		}
 
@@ -242,6 +245,8 @@ final class QRMatrixTest extends TestCase{
 
 		if($version < 7){
 			$this->markTestSkipped('N/A');
+
+			/** @noinspection PhpUnreachableStatementInspection */
 			return;
 		}
 
@@ -304,4 +309,69 @@ final class QRMatrixTest extends TestCase{
 		$this->matrix->setQuietZone();
 	}
 
+	public function testSetLogoSpaceOrientation():void{
+		$o = new QROptions;
+		$o->version      = 10;
+		$o->eccLevel     = QRCode::ECC_H;
+		$o->addQuietzone = false;
+
+		$matrix = (new QRCode($o))->getMatrix('testdata');
+		// also testing size adjustment to uneven numbers
+		$matrix->setLogoSpace(20, 14);
+
+		// NW corner
+		$this::assertNotSame(QRMatrix::M_LOGO, $matrix->get(17, 20));
+		$this::assertSame(QRMatrix::M_LOGO, $matrix->get(18, 21));
+
+		// SE corner
+		$this::assertSame(QRMatrix::M_LOGO, $matrix->get(38, 35));
+		$this::assertNotSame(QRMatrix::M_LOGO, $matrix->get(39, 36));
+	}
+
+	public function testSetLogoSpacePosition():void{
+		$o = new QROptions;
+		$o->version       = 10;
+		$o->eccLevel      = QRCode::ECC_H;
+		$o->addQuietzone  = true;
+		$o->quietzoneSize = 10;
+
+		$m = (new QRCode($o))->getMatrix('testdata');
+
+		// logo space should not overwrite quiet zone & function patterns
+		$m->setLogoSpace(21, 21, -10, -10);
+		$this::assertSame(QRMatrix::M_QUIETZONE, $m->get(9, 9));
+		$this::assertSame(QRMatrix::M_FINDER << 8, $m->get(10, 10));
+		$this::assertSame(QRMatrix::M_FINDER << 8, $m->get(16, 16));
+		$this::assertSame(QRMatrix::M_SEPARATOR, $m->get(17, 17));
+		$this::assertSame(QRMatrix::M_FORMAT << 8, $m->get(18, 18));
+		$this::assertSame(QRMatrix::M_LOGO, $m->get(19, 19));
+		$this::assertSame(QRMatrix::M_LOGO, $m->get(20, 20));
+		$this::assertNotSame(QRMatrix::M_LOGO, $m->get(21, 21));
+
+		// i just realized that setLogoSpace() could be called multiple times
+		// on the same instance and i'm not going to do anything about it :P
+		$m->setLogoSpace(21, 21, 45, 45);
+		$this::assertNotSame(QRMatrix::M_LOGO, $m->get(54, 54));
+		$this::assertSame(QRMatrix::M_LOGO, $m->get(55, 55));
+		$this::assertSame(QRMatrix::M_QUIETZONE, $m->get(67, 67));
+	}
+
+	public function testSetLogoSpaceInvalidEccException():void{
+		$this->expectException(QRCodeDataException::class);
+		$this->expectExceptionMessage('ECC level "H" required to add logo space');
+
+		(new QRCode)->getMatrix('testdata')->setLogoSpace(50, 50);
+	}
+
+	public function testSetLogoSpaceMaxSizeException():void{
+		$this->expectException(QRCodeDataException::class);
+		$this->expectExceptionMessage('logo space exceeds the maximum error correction capacity');
+
+		$o = new QROptions;
+		$o->version  = 5;
+		$o->eccLevel = QRCode::ECC_H;
+
+		(new QRCode($o))->getMatrix('testdata')->setLogoSpace(50, 50);
+	}
+
 }