diff --git a/src/add-ons/kernel/file_systems/udf/DiskStructures.cpp b/src/add-ons/kernel/file_systems/udf/DiskStructures.cpp
index d827ca615f..6f2b88fd47 100644
--- a/src/add-ons/kernel/file_systems/udf/DiskStructures.cpp
+++ b/src/add-ons/kernel/file_systems/udf/DiskStructures.cpp
@@ -312,11 +312,12 @@ udf_implementation_use_descriptor::dump() const
 	DUMP(implementation_use());
 }
 
-
 //----------------------------------------------------------------------
 // udf_partition_descriptor
 //----------------------------------------------------------------------
 
+const uint8 Udf::kMaxPartitionDescriptors = 2;
+
 void
 udf_partition_descriptor::dump() const
 {
diff --git a/src/add-ons/kernel/file_systems/udf/DiskStructures.h b/src/add-ons/kernel/file_systems/udf/DiskStructures.h
index 8910d8714c..05f38e66d4 100644
--- a/src/add-ons/kernel/file_systems/udf/DiskStructures.h
+++ b/src/add-ons/kernel/file_systems/udf/DiskStructures.h
@@ -688,6 +688,11 @@ private:
 } __attribute__((packed));
 
 
+/*! \brief Maximum number of partition descriptors to be found in volume
+	descriptor sequence, per UDF-2.50
+*/
+extern const uint8 kMaxPartitionDescriptors;
+
 /*! \brief Partition Descriptor
 
 	See also: ECMA 167 3/10.5