[Form 4] Duolingo, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Duolingo (DUOL) insider activity: Co‑Founder/CTO and director Severin Hacker reported multiple transactions on 10/20/2025. He acquired 10,000 Class A shares at $38.08 via option exercise and then executed open‑market sales of 10,000 shares in multiple trades at prices from $305.86 to $324.10. The sales were made under a Rule 10b5‑1 plan adopted on September 11, 2024.

He also reported the settlement of 60,000 performance‑based RSUs, with 31,770 shares withheld for taxes at $312.73. Following the reported transactions, direct holdings shown in Table I were 72 Class A shares. An additional 2,886,917 Class A shares are held indirectly by the SBH Trust, of which he is trustee.

Insights

Insider Transactions & Governance Analyst

Routine Form 4 with planned sales and equity settlements.

Severin Hacker exercised options to acquire 10,000 Class A shares at $38.08 and sold 10,000 shares the same day across multiple trades between $305.86 and $324.10. The filing states these sales were under a pre‑arranged Rule 10b5‑1 plan adopted on September 11, 2024.

Equity awards also moved: 60,000 PSUs were settled, and 31,770 shares were withheld for taxes at $312.73. Direct holdings after the trades were 72 Class A shares, with 2,886,917 Class A shares held indirectly by the SBH Trust.

These are standard administrative transactions. Actual market impact depends on trade size relative to daily volume and was not addressed in the excerpt.

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^*

Hacker Severin

(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)

X	Director	X	10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Tech Officer, Co-Founder

3. Date of Earliest Transaction (Month/Day/Year)
10/20/2025

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	10/20/2025		C		10,000	A	$38.08	10,072	D
Class A Common Stock	10/20/2025		S		100(1)	D	$305.86	9,972	D
Class A Common Stock	10/20/2025		S		600(1)	D	$307.5533(2)	9,372	D
Class A Common Stock	10/20/2025		S		500(1)	D	$309.064(3)	8,872	D
Class A Common Stock	10/20/2025		S		632(1)	D	$309.9395(4)	8,240	D
Class A Common Stock	10/20/2025		S		1,000(1)	D	$311.4282(5)	7,240	D
Class A Common Stock	10/20/2025		S		1,281(1)	D	$312.3748(6)	5,959	D
Class A Common Stock	10/20/2025		S		500(1)	D	$313.9338(7)	5,459	D
Class A Common Stock	10/20/2025		S		1,100(1)	D	$315.7867(8)	4,359	D
Class A Common Stock	10/20/2025		S		1,600(1)	D	$316.6356(9)	2,759	D
Class A Common Stock	10/20/2025		S		680(1)	D	$317.6838(10)	2,079	D
Class A Common Stock	10/20/2025		S		907(1)	D	$318.7262(11)	1,172	D
Class A Common Stock	10/20/2025		S		300(1)	D	$319.97(12)	872	D
Class A Common Stock	10/20/2025		S		400(1)	D	$321.7475(13)	472	D
Class A Common Stock	10/20/2025		S		300(1)	D	$323.0913(14)	172	D
Class A Common Stock	10/20/2025		S		100(1)	D	$324.1	72	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
Stock Option (Right to Buy)	$38.08	10/20/2025		M			10,000	(15)	12/02/2030	Class B Common Stock	10,000	$0	25,252	D
Class B Common Stock	(16)	10/20/2025		C		10,000		(16)	(16)	Class A Common Stock	10,000	$0	96,075	D
Class B Common Stock	(16)	10/20/2025		C			10,000	(16)	(16)	Class A Common Stock	10,000	$0	86,075	D
Performance-Based Restricted Stock Units	(17)(18)	10/20/2025		M			60,000	(17)(18)	06/21/2031	Class B Common Stock	60,000	$0	390,000	D
Class B Common Stock	(16)	10/20/2025		M		60,000		(16)	(16)	Class A Common Stock	60,000	$0	146,075	D
Class B Common Stock	(16)	10/20/2025		F			31,770	(16)	(16)	Class A Common Stock	31,770	$312.73	114,305	D
Class B Common Stock	(16)							(16)	(16)	Class A Common Stock	2,886,917		2,886,917	I	See footnote(19)

Explanation of Responses:

1. The sale was effected pursuant to the Reporting Person's Rule 10b5-1 trading plan adopted on September 11, 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 $307.18 to $307.89, 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 $308.61 to $309.24, 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 $309.71 to $310.18, 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.

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 $310.86 to $311.81, 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 $311.94 to $312.65, 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 $313.65 to $314.30, 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 $315.18 to $316.17, 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 $316.22 to $317.19, 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.

10. 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 $317.22 to $318.20, 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.

11. 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 $318.38 to $319.26, 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.

12. 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 $319.85 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.

13. 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 $321.32 to $322.19, 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.

14. 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 $322.98 to $323.25, 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.

15. The shares subject to the option are fully vested and exercisable.

16. 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 in connection with: (i) any transfer, whether or not for value, except for certain permitted transfers further described in the Issuer's amended and restated certificate of incorporation, (ii) such time as the aggregate number of shares of Class B Common Stock outstanding ceases to represent 5% of the aggregate number of shares of Common Stock outstanding, and (iii) the death of the Reporting Person.

17. Each Performance-Based Restricted Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Class B Common Stock upon vesting. The PSUs vest upon the satisfaction of both a service-based condition and a performance-based condition. The service-based condition is satisfied as to 25% of the PSUs on each anniversary of the completion of the Issuer's initial public offering of Class A common stock based on the Reporting Person's continuous service as CTO to the Issuer through the applicable vesting dates, subject to acceleration upon a cessation of service as CTO as a result of death or permanent disability.

18. The performance-based condition will be satisfied upon the Issuer's Class A common stock achieving certain stock price hurdles over a period of ten years. Vested PSUs will be settled by the issuance of the underlying Class B Common Stock on the first anniversary of vesting, subject to acceleration upon a termination of employment or a change in control of the Issuer.

19. Shares held by SBH Trust dated March 10, 2020, of which Reporting Person is Trustee.

Remarks:

	/s/ Stephen Chen, as Attorney-in-Fact for Severin Hacker	10/22/2025
	** 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 insider transactions did DUOL’s CTO report on 10/20/2025?

He exercised options to acquire 10,000 Class A shares at $38.08 and sold 10,000 shares in multiple trades between $305.86 and $324.10.

Were the DUOL insider sales under a Rule 10b5-1 plan?

Yes. The filing states the sales were made pursuant to a Rule 10b5‑1 trading plan adopted on September 11, 2024.

What equity awards were involved for DUOL’s CTO?

The report shows settlement of 60,000 performance‑based RSUs, with 31,770 shares withheld for taxes at $312.73.

What are the CTO’s DUOL holdings after the reported trades?

Table I shows 72 Class A shares held directly. An additional 2,886,917 Class A shares are held indirectly by the SBH Trust.

What roles does the reporting person hold at Duolingo (DUOL)?

He is a Director, 10% Owner, and Chief Tech Officer, and is a Co‑Founder.

What was the option exercise price reported?

The option exercise price reported was $38.08 for 10,000 shares.