diff --git a/src/UglyToad.PdfPig/Parser/PageFactory.cs b/src/UglyToad.PdfPig/Parser/PageFactory.cs
index 8345ba56..0637c1be 100644
--- a/src/UglyToad.PdfPig/Parser/PageFactory.cs
+++ b/src/UglyToad.PdfPig/Parser/PageFactory.cs
@@ -54,8 +54,8 @@
                 rotation = new PageRotationDegrees(rotateToken.Int);
             }
 
-            MediaBox mediaBox = GetMediaBox(number, dictionary, pageTreeMembers, isLenientParsing);
-            CropBox cropBox = GetCropBox(dictionary, pageTreeMembers, mediaBox, isLenientParsing);
+            MediaBox mediaBox = GetMediaBox(number, dictionary, pageTreeMembers);
+            CropBox cropBox = GetCropBox(dictionary, pageTreeMembers, mediaBox);
 
             var stackDepth = 0;
 
@@ -160,15 +160,15 @@
             return spaceUnits;
         }
 
-        private CropBox GetCropBox(DictionaryToken dictionary, PageTreeMembers pageTreeMembers, MediaBox mediaBox, bool isLenientParsing)
+        private CropBox GetCropBox(DictionaryToken dictionary, PageTreeMembers pageTreeMembers, MediaBox mediaBox)
         {
             CropBox cropBox;
             if (dictionary.TryGet(NameToken.CropBox, out var cropBoxObject) &&
                 DirectObjectFinder.TryGet(cropBoxObject, pdfScanner, out ArrayToken cropBoxArray))
             {
-                if (cropBoxArray.Length != 4 && isLenientParsing)
+                if (cropBoxArray.Length != 4)
                 {
-                    log.Error($"The CropBox was the wrong length in the dictionary: {dictionary}. Array was: {cropBoxArray}.");
+                    log.Error($"The CropBox was the wrong length in the dictionary: {dictionary}. Array was: {cropBoxArray}. Using MediaBox.");
                     
                     cropBox = new CropBox(mediaBox.Bounds);
 
@@ -185,17 +185,17 @@
             return cropBox;
         }
 
-        private MediaBox GetMediaBox(int number, DictionaryToken dictionary, PageTreeMembers pageTreeMembers, bool isLenientParsing)
+        private MediaBox GetMediaBox(int number, DictionaryToken dictionary, PageTreeMembers pageTreeMembers)
         {
             MediaBox mediaBox;
             if (dictionary.TryGet(NameToken.MediaBox, out var mediaboxObject) 
                 && DirectObjectFinder.TryGet(mediaboxObject, pdfScanner, out ArrayToken mediaboxArray))
             {
-                if (mediaboxArray.Length != 4 && isLenientParsing)
+                if (mediaboxArray.Length != 4)
                 {
-                    log.Error($"The MediaBox was the wrong length in the dictionary: {dictionary}. Array was: {mediaboxArray}.");
+                    log.Error($"The MediaBox was the wrong length in the dictionary: {dictionary}. Array was: {mediaboxArray}. Defaulting to US Letter.");
 
-                    mediaBox = MediaBox.A4;
+                    mediaBox = MediaBox.Letter;
 
                     return mediaBox;
                 }
@@ -208,14 +208,10 @@
 
                 if (mediaBox == null)
                 {
-                    if (isLenientParsing)
-                    {
-                        mediaBox = MediaBox.A4;
-                    }
-                    else
-                    {
-                        throw new InvalidOperationException("No mediabox was present for page: " + number);
-                    }
+                    log.Error($"The MediaBox was the wrong missing for page {number}. Using US Letter.");
+
+                    // PDFBox defaults to US Letter.
+                    mediaBox = MediaBox.Letter;
                 }
             }