[Form 4] Duolingo, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Natalie Glance, Chief Engineering Officer of Duolingo, Inc. (DUOL), reported multiple open-market sales of Class A common stock executed on 10/01/2025 pursuant to a Rule 10b5-1 trading plan adopted on 11/14/2024. The filings show nine sale entries totaling 3,283 shares sold at weighted-average prices reported in footnotes, with transaction price ranges between $303.45 and $320.21. Following these disposals, the reporting person directly beneficially owns 116,171 shares and indirectly owns 130 shares through a family member, for combined beneficial ownership of 116,301 shares.

Positive

• Sales executed under a Rule 10b5-1 plan, indicating preplanned transactions
• Substantial retained ownership after sales: 116,301 total shares

Negative

• Insider sold 3,283 shares on 10/01/2025, which reduces direct stake
• Weighted-average sale prices vary across transactions, creating less price transparency without broker breakdowns

Insights

Corporate Governance Specialist

Insider sales were executed under a pre-existing 10b5-1 plan and are routine for disclosed officers.

These sales were reported as occurring under a Rule 10b5-1 plan adopted on 11/14/2024, which provides an affirmative defense against insider trading claims when executed according to plan terms. The filing lists multiple tranches executed on 10/01/2025 with weighted-average sale prices described in footnotes.

The primary dependency is the plan's existence and timing; because the plan predates the sales, this reduces governance risk tied to opportunistic timing. Monitor any future Form 4s for additional plan activity or material changes in beneficial ownership within the next 30-90 days.

Equity Holdings Analyst

Total insider disposition was modest relative to total reported holdings, leaving substantial retained ownership.

The reported disposals total 3,283 shares sold across price ranges from $303.45 to $320.21, with the filer retaining a direct stake of 116,171 shares plus 130 indirect shares. The filing does not disclose the dollar value aggregated, only weighted-average price ranges in footnotes.

Watch for near-term changes in direct holdings reported on subsequent Forms; short-term market impact is likely limited given continued ownership of 116,301 shares.

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^*

Glance Natalie

(Last) (First) (Middle)

C/O DUOLINGO, INC.

5900 PENN AVENUE

(Street)

PITTSBURGH PA 15206

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Duolingo, Inc. [ DUOL ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
10/01/2025

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
Class A Common Stock	10/01/2025		S(1)		100	D	$300.56	119,354	D
Class A Common Stock	10/01/2025		S(1)		475	D	$303.7442(2)	118,879	D
Class A Common Stock	10/01/2025		S(1)		200	D	$305.09(3)	118,679	D
Class A Common Stock	10/01/2025		S(1)		600	D	$306.505(4)	118,079	D
Class A Common Stock	10/01/2025		S(1)		108	D	$312.7463(5)	117,971	D
Class A Common Stock	10/01/2025		S(1)		300	D	$315.2833(6)	117,671	D
Class A Common Stock	10/01/2025		S(1)		300	D	$316.7367(7)	117,371	D
Class A Common Stock	10/01/2025		S(1)		600	D	$317.955(8)	116,771	D
Class A Common Stock	10/01/2025		S(1)		600	D	$319.7567(9)	116,171	D
Class A Common Stock								130	I	By son

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. The sale was effected pursuant to the Reporting Person's Rule 10b5-1 trading plan adopted on November 14, 2024.

2. The price reported in Column 4 is a weighted average sale price calculated by the broker executing the sales. These shares were sold in multiple transactions at prices ranging from $303.45 to $304.06, inclusive. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote.

3. The price reported in Column 4 is a weighted average sale price calculated by the broker executing the sales. These shares were sold in multiple transactions at prices ranging from $305.00 to $305.18, inclusive. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote.

4. The price reported in Column 4 is a weighted average sale price calculated by the broker executing the sales. These shares were sold in multiple transactions at prices ranging from $306.00 to $306.99, inclusive. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote.

5. The price reported in Column 4 is a weighted average sale price calculated by the broker executing the sales. These shares were sold in multiple transactions at prices ranging from $312.71 to $313.20, inclusive. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote.

6. The price reported in Column 4 is a weighted average sale price calculated by the broker executing the sales. These shares were sold in multiple transactions at prices ranging from $315.01 to $315.65, inclusive. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote.

7. The price reported in Column 4 is a weighted average sale price calculated by the broker executing the sales. These shares were sold in multiple transactions at prices ranging from $316.41 to $316.90, inclusive. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote.

8. The price reported in Column 4 is a weighted average sale price calculated by the broker executing the sales. These shares were sold in multiple transactions at prices ranging from $317.51 to $318.33, inclusive. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote.

9. The price reported in Column 4 is a weighted average sale price calculated by the broker executing the sales. These shares were sold in multiple transactions at prices ranging from $319.46 to $320.21, inclusive. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote.

Remarks:

	/s/ Stephen Chen, as Attorney-in-Fact for Natalie Glance	10/03/2025
	** 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 Natalie Glance (DUOL) sell on 10/01/2025?

The report shows 3,283 Class A shares sold in multiple transactions executed on 10/01/2025 under a Rule 10b5-1 plan.

Were these sales part of a trading plan for DUOL insiders?

Yes. The sales were effected pursuant to a Rule 10b5-1 trading plan adopted on 11/14/2024, as stated in the Form 4.

How many DUOL shares does the reporting person own after the sales?

After the reported transactions the reporting person directly owns 116,171 shares and indirectly owns 130 shares, totaling 116,301 shares.

What price ranges were the shares sold at in the Form 4?

Footnotes disclose sale price ranges by tranche, spanning approximately $303.45 to $320.21, with weighted-average prices reported for each sale line.

Who signed the Form 4 for Natalie Glance?

The Form 4 was signed by Stephen Chen as Attorney-in-Fact for Natalie Glance on 10/03/2025.