DEXCOM INC — Director's Dealing 2013

May 13, 2013

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: DEXCOM INC (DXCM)
CIK: 0001093557
Period of Report: 2013-05-13

Reporting Person: Balo Andrew K (SVP, Regulatory and Clinical)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2013-05-13	Common Stock	M	45000	$2.4	Acquired	189571	Direct
2013-05-13	Common Stock	S	45000	$19.4	Disposed	144571	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2013-05-13	Incentive Stock Option (right to buy)	$2.4	M	45000	Disposed	2014-12-24	Common Stock (45000)	Direct

Footnotes

F1: Included in this number are 100,489 unvested restricted stock units, 14,656 of which were granted on March 8, 2011 and shall vest through March 8, 2014, 35,833 of which were granted on March 8, 2012 and shall vest through March 8, 2015 and 50,000 of which were granted on March 11, 2013 and shall vest through March 11, 2016.