[Form 4] DexCom, Inc. Insider Trading Activity

Rhea-AI Filing Summary

DexCom insider sale under 10b5-1 plan: Sylvain Jereme M., Executive Vice President and Chief Financial Officer of DexCom (DXCM), reported the sale of 4,824 shares of DexCom common stock on 09/02/2025 at an average price of $74.17 per share. The filing states the sales were made pursuant to a 10b5-1 trading plan adopted on May 27, 2025 to allow orderly dispositions. After the reported disposition, Mr. Sylvain beneficially owns 118,657 shares, which include 83,328 unvested restricted stock units with scheduled vesting through March 8, 2028.

Positive

• Sale executed under a documented 10b5-1 plan, indicating pre-planned and compliant disposition
• Detailed disclosure of unvested restricted stock units and vesting schedules improves transparency

Negative

• Insider sold 4,824 shares, reducing holdings though the amount is modest relative to total beneficial ownership

Insights

Securities Analyst

TL;DR: Officer sold a small portion of holdings under a pre-established 10b5-1 plan; remaining holdings include substantial unvested RSUs.

The reported sale of 4,824 shares at $74.17 was executed pursuant to a 10b5-1 plan adopted May 27, 2025, which provides an affirmative defense to insider trading claims by documenting pre-planned dispositions. The post-transaction beneficial ownership of 118,657 shares includes 83,328 unvested restricted stock units with staggered vesting through March 8, 2028, which limits immediate liquidity. This is a routine insider disposition consistent with planned tax or diversification transactions rather than an unscheduled trading event.

Corporate Governance Expert

TL;DR: Use of a 10b5-1 plan indicates compliance intent; transaction appears procedural rather than extraordinary.

The filing clearly indicates the transaction was executed under a documented 10b5-1 plan, adopted May 27, 2025, which supports compliance with insider-trading rules. The quantity sold (4,824 shares) is modest relative to total beneficial holdings (118,657 shares). The disclosure of detailed RSU vesting schedules enhances transparency about the composition of ownership and future potential dilution from vesting.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

X

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Sylvain Jereme M

(Last) (First) (Middle)

6340 SEQUENCE DRIVE

(Street)

SAN DIEGO CA 92121

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
DEXCOM INC [ DXCM ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	EVP, Chief Financal Officer

3. Date of Earliest Transaction (Month/Day/Year)
09/02/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	09/02/2025		S		4,824(1)	D	$74.17	118,657(2)	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. On May 27, 2025, Mr. Sylvain adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Sylvain. The shares set forth above were sold pursuant to the 10b5-1 Plan.

2. Included in this number are 83,328 unvested restricted stock units, 35,906 of which were granted on March 8, 2025 and shall vest through March 8, 2028, 22,798 of which were granted on March 8, 2025 and shall vest through March 8, 2027, 17,368 of which were granted on March 8, 2024 and shall vest through March 8, 2027, and 7,256 of which were granted on March 8, 2023 and shall vest through March 8, 2026.

Remarks:

	/s/ Jereme M. Sylvain	09/04/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What did DXCM insider Sylvain Jereme M. report on Form 4?

He reported the sale of 4,824 shares of DexCom common stock on 09/02/2025 at an average price of $74.17 per share.

Were the sales made under a trading plan for DXCM insider Sylvain Jereme M.?

Yes. The filing states the sales were made pursuant to a 10b5-1 plan adopted on May 27, 2025.

How many DexCom shares does Sylvain Jereme M. beneficially own after the transaction?

The Form 4 reports 118,657 shares beneficially owned following the reported disposition.

Does the filing disclose unvested equity for Sylvain Jereme M.?

Yes. It discloses 83,328 unvested restricted stock units with vesting schedules through March 8, 2028.

What is the role of Sylvain Jereme M. at DexCom?

He is listed as Executive Vice President, Chief Financial Officer of DexCom.