diff --git a/src/mathed/InsetMathOverset.cpp b/src/mathed/InsetMathOverset.cpp
index 9d835f0d9e..3d36218d63 100644
--- a/src/mathed/InsetMathOverset.cpp
+++ b/src/mathed/InsetMathOverset.cpp
@@ -70,6 +70,24 @@ bool InsetMathOverset::idxUpDown(Cursor & cur, bool up) const
 }
 
 
+bool InsetMathOverset::idxFirst(Cursor & cur) const
+{
+	LASSERT(&cur.inset() == this, return false);
+	cur.idx() = 0;
+	cur.pos() = 0;
+	return true;
+}
+
+
+bool InsetMathOverset::idxLast(Cursor & cur) const
+{
+	LASSERT(&cur.inset() == this, return false);
+	cur.idx() = 0;
+	cur.pos() = cur.lastpos();
+	return true;
+}
+
+
 void InsetMathOverset::write(WriteStream & os) const
 {
 	MathEnsurer ensurer(os);
diff --git a/src/mathed/InsetMathOverset.h b/src/mathed/InsetMathOverset.h
index eb6b86b798..213c96f5b3 100644
--- a/src/mathed/InsetMathOverset.h
+++ b/src/mathed/InsetMathOverset.h
@@ -30,6 +30,10 @@ public:
 	///
 	bool idxUpDown(Cursor & cur, bool up) const;
 	///
+	bool idxFirst(Cursor &) const;
+	///
+	bool idxLast(Cursor &) const;
+	///
 	void write(WriteStream & os) const;
 	///
 	void normalize(NormalStream &) const;
diff --git a/src/mathed/InsetMathStackrel.cpp b/src/mathed/InsetMathStackrel.cpp
index 9a9c66f24c..430d8f1ad2 100644
--- a/src/mathed/InsetMathStackrel.cpp
+++ b/src/mathed/InsetMathStackrel.cpp
@@ -19,6 +19,8 @@
 #include "LaTeXFeatures.h"
 #include "MetricsInfo.h"
 
+#include "support/lassert.h"
+
 using namespace std;
 
 namespace lyx {
@@ -54,6 +56,24 @@ bool InsetMathStackrel::idxUpDown(Cursor & cur, bool up) const
 }
 
 
+bool InsetMathStackrel::idxFirst(Cursor & cur) const
+{
+	LASSERT(&cur.inset() == this, return false);
+	cur.idx() = 0;
+	cur.pos() = 0;
+	return true;
+}
+
+
+bool InsetMathStackrel::idxLast(Cursor & cur) const
+{
+	LASSERT(&cur.inset() == this, return false);
+	cur.idx() = 0;
+	cur.pos() = cur.lastpos();
+	return true;
+}
+
+
 MathClass InsetMathStackrel::mathClass() const
 {
 	// FIXME: update this when/if \stackbin is supported
diff --git a/src/mathed/InsetMathStackrel.h b/src/mathed/InsetMathStackrel.h
index d6ac815182..5740fb922b 100644
--- a/src/mathed/InsetMathStackrel.h
+++ b/src/mathed/InsetMathStackrel.h
@@ -24,6 +24,10 @@ public:
 	///
 	bool idxUpDown(Cursor &, bool up) const;
 	///
+	bool idxFirst(Cursor &) const;
+	///
+	bool idxLast(Cursor &) const;
+	///
 	MathClass mathClass() const;
 	///
 	void metrics(MetricsInfo & mi, Dimension & dim) const;
diff --git a/src/mathed/InsetMathUnderset.cpp b/src/mathed/InsetMathUnderset.cpp
index 794427e2c2..832631dfa3 100644
--- a/src/mathed/InsetMathUnderset.cpp
+++ b/src/mathed/InsetMathUnderset.cpp
@@ -19,6 +19,7 @@
 #include "LaTeXFeatures.h"
 #include "MetricsInfo.h"
 
+#include "support/lassert.h"
 
 using namespace std;
 
@@ -58,6 +59,24 @@ void InsetMathUnderset::draw(PainterInfo & pi, int x, int y) const
 }
 
 
+bool InsetMathUnderset::idxFirst(Cursor & cur) const
+{
+	LASSERT(&cur.inset() == this, return false);
+	cur.idx() = 0;
+	cur.pos() = 0;
+	return true;
+}
+
+
+bool InsetMathUnderset::idxLast(Cursor & cur) const
+{
+	LASSERT(&cur.inset() == this, return false);
+	cur.idx() = 0;
+	cur.pos() = cur.lastpos();
+	return true;
+}
+
+
 void InsetMathUnderset::write(WriteStream & os) const
 {
 	MathEnsurer ensurer(os);
diff --git a/src/mathed/InsetMathUnderset.h b/src/mathed/InsetMathUnderset.h
index fbc3e779de..50143ae4d5 100644
--- a/src/mathed/InsetMathUnderset.h
+++ b/src/mathed/InsetMathUnderset.h
@@ -28,6 +28,10 @@ public:
 	///
 	void draw(PainterInfo & pi, int x, int y) const;
 	///
+	bool idxFirst(Cursor &) const;
+	///
+	bool idxLast(Cursor &) const;
+	///
 	void write(WriteStream & ws) const;
 	///
 	void normalize(NormalStream & ns) const;