Form 4: Duolingo CTO Sells Shares Under 10b5-1 Plan

Duolingo Co-Founder and CTO Severin Hacker sold 10,000 shares of Class A Common Stock for over $1.7 million through a pre-arranged trading plan.

Summary

• Severin Hacker, Duolingo's Chief Technology Officer, Co-Founder, Director, and 10% Owner, reported transactions involving Duolingo, Inc. Class A Common Stock.
• On November 19, 2025, Hacker exercised 10,000 stock options for Class B Common Stock at an exercise price of $38.08 per share.
• Concurrently, 10,000 shares of Class B Common Stock were converted into 10,000 shares of Class A Common Stock.
• Following the conversion, Hacker sold a total of 10,000 shares of Class A Common Stock in multiple transactions on November 19, 2025.
• The sales were executed at weighted average prices ranging from $169.5673 to $176.6814 per share.
• These sales were conducted pursuant to a Rule 10b5-1 trading plan adopted on September 11, 2024.
• After these transactions, Hacker directly beneficially owns 72 shares of Class A Common Stock.
• Hacker also continues to directly own 5,252 stock options for Class B Common Stock and indirectly owns 2,886,917 shares of Class B Common Stock through the SBH Trust dated March 10, 2020.

Sentiment

Score: 5

Explanation: The filing reports a pre-scheduled insider sale, which is a routine event for executives diversifying holdings and not indicative of company performance. The sentiment is neutral as it's a planned transaction rather than a reaction to new company-specific news.

Positives

• The sales were conducted under a pre-arranged Rule 10b5-1 trading plan, indicating a planned diversification of assets rather than a reaction to new negative information.
• The sale prices for the Class A Common Stock were significantly higher than the option exercise price of $38.08, demonstrating a substantial gain for the insider.

Negatives

• Insider selling, even if planned, reduces the direct ownership stake of a key executive and co-founder in the company's Class A Common Stock.

Risks

• No specific risks were mentioned in this Form 4 filing beyond the general implications of insider selling, which can sometimes be misinterpreted by the market if not understood as part of a pre-planned strategy.

Future Outlook

This Form 4 filing does not contain any forward-looking statements or guidance regarding the company's future performance or outlook.

Management Comments

• The sale was effected pursuant to the Reporting Person's Rule 10b5-1 trading plan adopted on September 11, 2024.
• 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 reported ranges.

Industry Context

Insider sales, particularly by founders and executives, are a common occurrence in the technology industry as individuals seek to diversify their personal wealth. The use of a Rule 10b5-1 trading plan is standard practice to execute such sales in a pre-scheduled manner, mitigating concerns about trading on material non-public information.

Comparison to Industry Standards

• The execution of sales under a Rule 10b5-1 plan aligns with best practices for corporate insiders to manage personal liquidity and wealth diversification while adhering to SEC regulations regarding insider trading. This is a widely adopted mechanism across publicly traded companies, including those in the tech sector like Duolingo.
• The reported transactions, involving the exercise of options and subsequent sale of shares, are typical for executives whose compensation includes equity awards that vest over time.

Corporate Governance

Related Party Transactions

• Shares of Class B Common Stock are indirectly held by the SBH Trust dated March 10, 2020, of which the Reporting Person, Severin Hacker, is the Trustee.

Stakeholder Impact

• Shareholders: May observe a reduction in direct insider ownership, but the pre-planned nature of the sale under a 10b5-1 plan typically mitigates concerns about management's confidence in the company.
• Employees: No direct impact mentioned, but general market perception of insider activity can sometimes influence employee sentiment.

Next Steps

• The Reporting Person has undertaken to provide detailed information on the specific sale prices within the reported ranges upon request from the SEC, the Issuer, or a security holder.

Key Dates

Recommendation

The reported insider sale by a co-founder and CTO was executed under a pre-arranged 10b5-1 trading plan, which is a common practice for executives to manage personal liquidity and diversify holdings. This type of transaction does not typically signal a change in the company's fundamental outlook or warrant an immediate change in investment recommendation. Investors should monitor for broader patterns of insider activity or other material news, but this single, planned transaction does not alter the investment thesis.

Keywords

Duolingo, DUOL, Severin Hacker, insider trading, Form 4, stock sale, 10b5-1 plan, CTO, beneficial ownership, Class A Common Stock, Class B Common Stock, stock options