DEXCOM INC — Director's Dealing 2012

Oct 5, 2012

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: DEXCOM INC (DXCM)
CIK: 0001093557
Period of Report: 2012-10-03

Reporting Person: GREGG TERRANCE H (Director, CEO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2012-10-03	Common Stock	S	5000	$14.93	Disposed	935889	Indirect

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	30000	Direct
Common Stock	11461	Indirect

Footnotes

F1: On November 21, 2011, Mr. Gregg adopted a 10b5-1 Plan. Under the 10b5-1 Plan, Mr. Gregg will sell a limited number of shares to cover the tax liability that accrues upon monthly vesting of restricted stock units previously granted to Mr. Gregg. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F2: Included in this number are 24,375 unvested restricted stock units granted on March 12, 2010, 4,062 of which shall vest each month through March 12, 2013; 91,407 unvested restricted stock units granted on March 8, 2011, 5,078 of which shall vest each month through March 8, 2014; and 152,345 unvested restricted stock units granted on March 8, 2012, 5,078 of which shall vest each month through March 8, 2015.

F3: Shares are held by the Gregg Family Trust U/A/D 12/23/1998, with respect to which the reporting person is a trustee.