diff --git a/SabreTools.Library/DatItems/Rom.cs b/SabreTools.Library/DatItems/Rom.cs
index 66fa4727..0738f69b 100644
--- a/SabreTools.Library/DatItems/Rom.cs
+++ b/SabreTools.Library/DatItems/Rom.cs
@@ -293,6 +293,18 @@ namespace SabreTools.Library.DatItems
                 dupefound = false;
             }
 
+            // If we have a file that has no known size, rely on the hashes only
+            else if ((this.Size == -1)
+                && ((this._crc.IsNullOrWhiteSpace() || newOther._crc.IsNullOrWhiteSpace()) || Enumerable.SequenceEqual(this._crc, newOther._crc))
+                && ((this._md5.IsNullOrWhiteSpace() || newOther._md5.IsNullOrWhiteSpace()) || Enumerable.SequenceEqual(this._md5, newOther._md5))
+                && ((this._sha1.IsNullOrWhiteSpace() || newOther._sha1.IsNullOrWhiteSpace()) || Enumerable.SequenceEqual(this._sha1, newOther._sha1))
+                && ((this._sha256.IsNullOrWhiteSpace() || newOther._sha256.IsNullOrWhiteSpace()) || Enumerable.SequenceEqual(this._sha256, newOther._sha256))
+                && ((this._sha384.IsNullOrWhiteSpace() || newOther._sha384.IsNullOrWhiteSpace()) || Enumerable.SequenceEqual(this._sha384, newOther._sha384))
+                && ((this._sha512.IsNullOrWhiteSpace() || newOther._sha512.IsNullOrWhiteSpace()) || Enumerable.SequenceEqual(this._sha512, newOther._sha512)))
+            {
+                dupefound = true;
+            }
+
             // Otherwise if we get a partial match
             else if ((this.Size == newOther.Size)
                 && ((this._crc.IsNullOrWhiteSpace() || newOther._crc.IsNullOrWhiteSpace()) || Enumerable.SequenceEqual(this._crc, newOther._crc))