[Form 4] Duolingo, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Form 4 highlights for Duolingo (DUOL): Co-founder, CTO, director and >10% owner Severin Hacker reported a series of insider transactions dated 8 Aug 2025.

• Option exercise: 10,000 Class B options exercised at $38.08 (cost ~$0.38 M).
• Conversions: Two line-items show 20,000 Class B shares converted to Class A; 10,000 of the converted shares were immediately sold.
• Sales: 10,000 Class A shares sold in 12 tranches between $338.80–$355.15; volume-weighted average ≈ $344, generating proceeds of roughly $3.4 M. Sales were executed under a Rule 10b5-1 plan adopted 11 Sep 2024.
• Post-trade ownership: Direct Class A stake falls to 72 shares; direct derivative holdings total 86,075 options; indirect trust continues to hold 2,896,917 Class B shares, underscoring continued majority control.

No earnings data or company guidance is included; the filing solely documents routine insider activity. Given the small size of the sale relative to Hacker’s remaining 2.9 M-share economic interest, market impact is likely limited.

Insights

Securities Analyst

TL;DR: 10k-share sale by CTO is modest vs. 2.9 M retained, suggesting limited strategic signal.

The filing shows a classic exercise-and-sell: options struck at $38.08 were exercised, converted and sold at ≈$344, yielding a 9× gain. Transaction size (~$3.4 M) represents <1% of Hacker’s overall economic stake, and execution under a pre-arranged 10b5-1 plan diminishes informational value. Insider still controls nearly 3 M super-voting Class B shares, so governance dynamics are unchanged. I view the disclosure as neutral; it neither indicates operational weakness nor materially alters float.

Portfolio Manager

TL;DR: Routine liquidity event; float increase minimal, sentiment mildly negative but not thesis-changing.

From a portfolio standpoint, insider selling can pressure sentiment, yet the 10k shares equate to <0.03% of DUOL’s ~34 M Class A float. Execution spread across 12 price tiers limits market impact. Continued lock on 2.9 M Class B shares preserves founder influence—no governance shift to factor into position sizing. I assign a neutral impact; however, repeated sales could become a trend worth monitoring.

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)
08/05/2025

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	08/05/2025		C		10,000	A	$38.08	10,072	D
Class A Common Stock	08/05/2025		S(1)		403	D	$339.3173(2)	9,669	D
Class A Common Stock	08/05/2025		S(1)		2,098	D	$340.276(3)	7,571	D
Class A Common Stock	08/05/2025		S(1)		1,330	D	$341.5468(4)	6,241	D
Class A Common Stock	08/05/2025		S(1)		2,205	D	$342.5619(5)	4,036	D
Class A Common Stock	08/05/2025		S(1)		600	D	$343.4317(6)	3,436	D
Class A Common Stock	08/05/2025		S(1)		1,133	D	$344.9857(7)	2,303	D
Class A Common Stock	08/05/2025		S(1)		200	D	$346.73(8)	2,103	D
Class A Common Stock	08/05/2025		S(1)		300	D	$349.2467(9)	1,803	D
Class A Common Stock	08/05/2025		S(1)		200	D	$351.075(10)	1,603	D
Class A Common Stock	08/05/2025		S(1)		200	D	$352.745(11)	1,403	D
Class A Common Stock	08/05/2025		S(1)		931	D	$354.4462(12)	472	D
Class A Common Stock	08/05/2025		S(1)		400	D	$355.0625(13)	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	08/05/2025		M			10,000	(14)	12/02/2030	Class B Common Stock	10,000	$0	75,252	D
Class B Common Stock	(15)	08/05/2025		C		10,000		(15)	(15)	Class A Common Stock	10,000	$0	96,075	D
Class B Common Stock	(15)	08/05/2025		C			10,000	(15)	(15)	Class A Common Stock	10,000	$0	86,075	D
Class B Common Stock	(15)							(15)	(15)	Class A Common Stock	2,896,917		2,896,917	I	See footnote(16)

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 $338.80 to $339.57, 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 $339.81 to $340.77, 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 $341.06 to $341.93, 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 $342.08 to $342.91, 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 $343.22 to $343.72, 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 $344.47 to $345.31, 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 $346.71 to $346.75, 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 $348.76 to $349.49, 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 $351.05 to $351.10, 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 $352.50 to $352.99, 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.

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 $353.94 to $354.82, 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 $355.01 to $355.15, 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 shares subject to the option are fully vested and exercisable.

15. 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.

16. 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	08/07/2025
	** 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

How many Duolingo (DUOL) shares did Severin Hacker sell on 08/05/2025?

10,000 Class A shares were sold in multiple tranches.

What was the average sale price of the DUOL shares?

Weighted average price was roughly $344 per share, with trades from $338.80 to $355.15.

Did the insider exercise stock options before selling?

Yes, he exercised 10,000 options at $38.08 and converted the resulting Class B shares to Class A.

How many shares does Severin Hacker still own after the transaction?

Direct holding: 72 Class A; indirect trust: 2,896,917 Class B; plus 86,075 option shares.

Was the sale executed under a 10b5-1 trading plan?

Yes, the filing states the transactions were under a Rule 10b5-1 plan adopted 09/11/2024.