10. Long-term Debt

A summary of Long-term Debt follows:


			(Stated in millions)
	Jun. 30, 2013		Dec. 31 2012
3.30% Senior Notes due 2021	$	1,596	$	1,595
4.50% Guaranteed Notes due 2014		—		1,324
2.75% Guaranteed Notes due 2015		1,302		1,318
1.95% Senior Notes due 2016		1,099		1,099
4.20% Senior Notes due 2021		1,099		1,099
1.25% Senior Notes due 2017		999		999
2.40% Senior Notes due 2022		998		998
2.65% Senior Notes due 2016		500		500
Floating Rate Senior Notes due 2014		300		300
Commercial paper borrowings		650		—
Other		555		277

	$	9,098	$	9,509

The estimated fair value of Schlumberger’s Long-term Debt at June 30, 2013 and December 31, 2012, based on quoted market prices, was $9.2 billion and $9.9 billion, respectively.