[Form 4] Datadog, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Datadog director Michael James Callahan reported a mix of share conversion and sales involving trust-held stock. A trust for his benefit converted 12,500 shares of Class B Common Stock into 12,500 shares of Class A Common Stock, then sold 12,500 Class A shares at $267.47 per share in an open-market transaction pursuant to a Rule 10b5-1 trading plan dated March 13, 2026.

After these transactions, Callahan holds 20,684 Class A shares directly and, through the Callahan-Thernstrom Family Trust where he serves as trustee, 27,496 Class A shares and 98,042 Class B shares. The filing shows both ongoing equity ownership and routine, pre-planned liquidity activity.

Insights

Equity compensation and insider-trading analyst

Director’s trust converts and sells shares under a pre-planned Rule 10b5-1 program while retaining a substantial stake.

The transactions show the Callahan-Thernstrom Family Trust converting 12,500 Class B shares into 12,500 Class A shares, then selling 12,500 Class A shares at $267.47. The sale is coded as an open-market transaction and explicitly tied to a Rule 10b5-1 plan dated March 13, 2026, indicating it was pre-scheduled.

Afterward, Michael James Callahan still holds 20,684 Class A shares directly, plus 27,496 Class A and 98,042 Class B shares through the trust. This pattern—conversion paired with a pre-planned sale while maintaining sizable holdings—typically reflects routine portfolio management rather than a major strategic shift. Future company filings will continue to update his remaining positions.

Insider Trade Summary 10b5-1

Net Seller: 12,500 shares ($3,343,375)

Net Sell 4 txns

Insider Callahan Michael James

Role null

Sold 12,500 shs ($3.34M)

Type	Security	Shares	Price	Value
Conversion	Class B Common Stock	12,500	$0.00	--
Conversion	Class A Common Stock	12,500	$0.00	--
Sale	Class A Common Stock	12,500	$267.47	$3.34M
holding	Class A Common Stock	--	--	--

Holdings After Transaction: Class B Common Stock — 98,042 shares (Indirect, By Trust); Class A Common Stock — 27,496 shares (Indirect, By Trust); Class A Common Stock — 20,684 shares (Direct, null)

Footnotes (1)

1. Each share of Class B Common Stock is convertible at any time at the option of the Reporting Person into one share of Class A Common Stock and has no expiration date. Each share of Class B Common Stock will convert automatically into one share of Class A Common Stock upon the earliest of: (i) any transfer, whether or not for value, except for certain "Permitted Transfers" as defined in the Issuer's amended and restated certificate of incorporation, (ii) the death of the Reporting Person in the case of shares held directly or in a trustee capacity, and (iii) the tenth anniversary of the Issuer's initial public offering of its Class A Common Stock. The Shares are held by The Callahan-Thernstrom Family Trust, of which Reporting Person is Trustee. Shares sold pursuant to a 10b5-1 plan dated March 13, 2026.

Key Figures

Class A shares sold: 12,500 shares Sale price per share: $267.47/share Class B converted: 12,500 shares +3 more

6 metrics

Class A shares sold 12,500 shares Open-market sale by Callahan-Thernstrom Family Trust

Sale price per share $267.47/share Class A Common Stock sale on 2026-07-01

Class B converted 12,500 shares Class B to Class A conversion by trust

Direct Class A holdings 20,684 shares Held directly by Michael James Callahan after transactions

Trust Class A holdings 27,496 shares Held by Callahan-Thernstrom Family Trust after transactions

Trust Class B holdings 98,042 shares Remaining Class B shares held by trust after conversion

Key Terms

Rule 10b5-1, Class B Common Stock, conversion of derivative security, open-market sale, +1 more

5 terms

Rule 10b5-1 regulatory

"Shares sold pursuant to a 10b5-1 plan dated March 13, 2026."

Rule 10b5-1 is a regulation that allows company insiders to buy or sell their shares at predetermined times, even if they have access to non-public information. It acts like setting a schedule in advance for transactions, helping prevent accusations of unfair trading. This rule provides a way for insiders to plan trades transparently, giving investors confidence that these transactions are not based on hidden information.

Class B Common Stock financial

"Each share of Class B Common Stock is convertible at any time..."

A class B common stock is one of multiple types of a company’s ordinary shares that carries specific rights—often different voting power or dividend priority—compared with other classes. For investors it matters because those differences affect how much influence you have over company decisions, the income you might receive, and how freely the shares trade; think of it like owning a car with different keys: some keys let you start the engine and open the trunk, others only unlock the door.

conversion of derivative security financial

"transaction_action": "derivative conversion""

open-market sale financial

"transaction_action": "open-market sale""

An open-market sale is when a shareholder sells existing shares directly on a public exchange to any willing buyer, rather than through a private deal. Think of it like putting goods on a busy market stall where price is set by supply and demand; for investors it matters because such sales increase available supply, can put short-term downward pressure on the stock price, and signal changes in liquidity or investor confidence.

family trust financial

"The Shares are held by The Callahan-Thernstrom Family Trust, of which Reporting Person is Trustee."

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Form 4 Insider Transactions: What Each Field Means →

Available on EDGAR 07/06/2026 - 05:54 PM Accepted by SEC EDGAR 07/06/2026 - 05:54 PM Learn about SEC filing dates

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^*

Callahan Michael James

(Last) (First) (Middle)

C/O DATADOG, INC.

620 8TH AVENUE, 45TH FLOOR

(Street)

NEW YORK NEW YORK 10018

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Datadog, Inc. [ DDOG ]

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

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
07/01/2026

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

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

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

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
Class A Common Stock	07/01/2026		C		12,500	A	(1)	27,496	I	By Trust(2)
Class A Common Stock	07/01/2026		S(3)		12,500	D	$267.47	14,996	I	By Trust(2)
Class A Common Stock								20,684	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
Class B Common Stock	(1)	07/01/2026		C			12,500	(1)	(1)	Class A Common Stock	12,500	$0	98,042	I	By Trust(2)

Explanation of Responses:

1. Each share of Class B Common Stock is convertible at any time at the option of the Reporting Person into one share of Class A Common Stock and has no expiration date. Each share of Class B Common Stock will convert automatically into one share of Class A Common Stock upon the earliest of: (i) any transfer, whether or not for value, except for certain "Permitted Transfers" as defined in the Issuer's amended and restated certificate of incorporation, (ii) the death of the Reporting Person in the case of shares held directly or in a trustee capacity, and (iii) the tenth anniversary of the Issuer's initial public offering of its Class A Common Stock.

2. The Shares are held by The Callahan-Thernstrom Family Trust, of which Reporting Person is Trustee.

3. Shares sold pursuant to a 10b5-1 plan dated March 13, 2026.

Remarks:

	/s/ Kerry Acocella, Attorney-in-Fact	07/06/2026
	** 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.
* Form 4: SEC 1474 (03-26)