diff --git a/include/jtag/part.h b/include/jtag/part.h
index 92b942f9..98b49ced 100644
--- a/include/jtag/part.h
+++ b/include/jtag/part.h
@@ -29,6 +29,7 @@
 
 #include <jtag/signal.h>
 #include <jtag/instruction.h>
+#include <jtag/data_register.h>
 #include <jtag/bsbit.h>
 
 typedef struct part part;
@@ -38,6 +39,7 @@ struct part {
 	int instruction_length;
 	instruction *instructions;
 	instruction *active_instruction;
+	data_register *data_registers;
 	int boundary_length;
 	bsbit **bsbits;
 	tap_register *idr;
diff --git a/jtag/src/part/part.c b/jtag/src/part/part.c
index 2386159d..e4755359 100644
--- a/jtag/src/part/part.c
+++ b/jtag/src/part/part.c
@@ -40,6 +40,7 @@ part_alloc( void )
 	p->instruction_length = 0;
 	p->instructions = NULL;
 	p->active_instruction = NULL;
+	p->data_registers = NULL;
 	p->boundary_length = 0;
 	p->bsbits = NULL;
 	p->idr = NULL;
@@ -71,6 +72,12 @@ part_free( part *p )
 		instruction_free( i );
 	}
 
+	while (p->data_registers) {
+		data_register *dr = p->data_registers;
+		p->data_registers = dr->next;
+		data_register_free( dr );
+	}
+
 	/* bsbits */
 	for (i = 0; i < p->boundary_length; i++)
 		bsbit_free( p->bsbits[i] );