HACKER SEVERIN (Chief Technology Officer,) reported 2 transactions at DUOLINGO, INC.

Review the transaction codes below to understand the nature of each event.

HACKER SEVERIN

Filed: 12/9/2025ACC: 0001628280-25-056204

InsiderHACKER SEVERINCIK 1870272

→

IssuerDUOLINGO, INC.CIK 1562088

DirectorOfficer10% OwnerOther· Chief Technology Officer,

Since Jul 2021

-50K

Net shares

Net seller

$0.00

Total acquired

Open market trades

0B · 0S

Total transactions

50K acquired · 100K disposed

Non-Derivative Transactions2

Class A Common Stock

Direct

C · Conversion

+50K

Price / share

—

Trade value

—

% of position

69444.4%

12/8/2025

72.00→50.07K

Class A Common Stock

Direct

G · Gift

−50K

Price / share

—

Trade value

—

% of position

99.9%

12/8/2025

50.07K→72.00

Total

Net shares

+0.00

Net value

$0.00

Security	Date	Type	Shares	Price / Share	Trade Value	% of Position	Held Before	Held After
Class A Common Stock Direct	12/8/2025	C · Conversion	+50K	—	—	69444.4%	72.00	50.07K
Class A Common Stock Direct	12/8/2025	G · Gift	−50K	—	—	99.9%	50.07K	72.00
Total			+0.00		$0.00

Derivative Transactions1

Class B Common Stock

Indirect

C · Conversion

Converts to

Class A Common Stock

50K shares

−50K

Strike price

Held after

2.84M

Exercisable

—

12/8/2025

Security	Converts To	Date	Type	Shares	Strike Price	Exercisable	Held After
Class B Common Stock Indirect	Class A Common Stock50K shares	12/8/2025	C · Conversion	−50K		—	2.84M

Non-Derivative Holdings (Post-Transaction)0

No non-derivative holdings reported

Derivative Holdings (Post-Transaction)1

Class B Common Stock

Direct

Underlying security

Class A Common Stock

Underlying shares

147.79K

Shares owned

147.79K

Exercise price

Expiration

—

Exercise window

—

Total

Underlying

147.79K

Owned

147.79K

Security	Underlying	Exercise Price	Exercise Window	Expiration	Underlying Shares	Shares Owned
Class B Common Stock Direct	Class A Common Stock		—	—	147.79K	147.79K
Total					147.79K	147.79K