DEXCOM INC — Director's Dealing 2018

May 9, 2018

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: DEXCOM INC (DXCM)
CIK: 0001093557
Period of Report: 2018-05-08

Reporting Person: SKYLER JAY S (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2018-05-08	Common Stock	M	31464	$7.63	Acquired	53721	Indirect
2018-05-08	Common Stock	S	31464	$85.1139	Disposed	22257	Indirect

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2018-05-08	Non-Qualified Stock Option (right to buy)	$7.63	M	31464	Disposed	2018-05-19	Common Stock (31464)	Indirect

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	4553	Direct
Common Stock	10000	Indirect

Footnotes

F1: Shares are held by Skyler Bach Family Limited Partnership, LLP, with respect to which the reporting person is a managing partner of the partnership and maintains voting rights of these shares.

F2: This transaction was executed in multiple trades at prices ranging from $84.85 to $85.52. The price above reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transactions were effected.

F3: The reporting person disclaims beneficial ownership of these securities and this report shall not be deemed an admission that the reporting person is the beneficial owner of the securities for purposes of Section 16 or for any other purpose.