Form 4: Duolingo Co-Founder Severin Hacker Exercises Options and Sells Shares Under Pre-Arranged Plan

Duolingo's Chief Technology Officer and Co-Founder, Severin Hacker, exercised stock options and subsequently sold 9,920 shares of Class A Common Stock under a Rule 10b5-1 trading plan.

Summary

• Severin Hacker, Duolingo's Chief Technology Officer, Co-Founder, Director, and 10% Owner, engaged in multiple transactions involving Duolingo Class A and Class B Common Stock on July 21, 2025.
• Hacker exercised 10,000 stock options at a strike price of $38.08 per share, which were fully vested and exercisable, resulting in the acquisition of Class B Common Stock.
• He converted 10,000 shares of Class B Common Stock into Class A Common Stock at a price of $38.08 per share.
• Following this acquisition, his direct beneficial ownership of Class A Common Stock was 10,072 shares.
• Hacker then sold a total of 9,920 shares of Class A Common Stock across multiple transactions on the same day.
• The sales were executed at weighted average prices ranging from $355.3063 to $370.05 per share.
• These sales were conducted pursuant to a Rule 10b5-1 trading plan adopted on September 11, 2024.
• After all reported transactions, Hacker's direct beneficial ownership of Class A Common Stock decreased to 72 shares.
• He continues to hold significant Class B Common Stock, including 2,896,917 shares indirectly through the SBH Trust dated March 10, 2020, of which he is the Trustee.

Sentiment

Score: 4

Explanation: The sentiment is slightly negative due to significant insider selling by a co-founder and CTO. While the sales were pre-planned under a 10b5-1 plan, which mitigates some concern, large insider dispositions can still create negative market perception. The exercise of options at a low strike price indicates prior confidence, but the immediate sale of the resulting shares suggests a liquidity event rather than a vote of confidence in future price appreciation.

Positives

• The exercise of stock options at a low strike price of $38.08 indicates a significant unrealized gain and prior confidence in the company's value.

Negatives

• The sale of 9,920 shares of Class A Common Stock by a key insider, even under a pre-arranged plan, can be perceived negatively by the market as it reduces the insider's direct stake.

Future Outlook

No forward-looking statements or guidance were provided in this filing.

Industry Context

This filing details an insider transaction, which is a routine disclosure for publicly traded companies. It does not provide broader industry context or trends.

Related Party Transactions

• Severin Hacker indirectly holds 2,896,917 shares of Class B Common Stock through the SBH Trust dated March 10, 2020, of which he is the Trustee.

Stakeholder Impact

• Shareholders may view the significant insider selling as a negative signal, potentially impacting investor confidence and the company's share price.

Key Dates

Recommendation

While the significant insider selling by a co-founder and CTO could be a cause for concern, the transactions were executed under a pre-arranged Rule 10b5-1 trading plan, which suggests a planned liquidity event rather than a reaction to new negative information. The exercise of options at a low strike price also indicates prior confidence. Investors should monitor future filings and company performance rather than reacting solely to this planned sale.

Keywords

Duolingo, DUOL, Severin Hacker, Insider Trading, Form 4, Stock Option Exercise, Share Sale, 10b5-1 Plan, Class A Common Stock, Class B Common Stock