Form 4: Klaviyo Co-CEO Bialecki Sells Shares Under 10b5-1 Plan

Klaviyo Co-CEO Andrew Bialecki executed a pre-planned sale of 155,219 Series A Common Stock shares on January 27, 2026, following a conversion from Series B shares.

Summary

• Andrew Bialecki, Co-Chief Executive Officer, Director, and 10% Owner of Klaviyo, Inc. (KVYO), reported transactions involving the company's stock.
• On January 27, 2026, Mr. Bialecki converted 155,219 shares of Series B Common Stock into an equal number of Series A Common Stock.
• Immediately following the conversion, Mr. Bialecki sold 150,689 shares of Series A Common Stock at a weighted average price of $25.34 per share, with prices ranging from $25.01 to $26.00.
• An additional 4,530 shares of Series A Common Stock were sold at a weighted average price of $24.94 per share, with prices ranging from $24.82 to $25.00.
• These transactions were conducted pursuant to a Rule 10b5-1 trading plan adopted by Mr. Bialecki on May 20, 2025.
• Following these transactions, Mr. Bialecki directly owns 0 shares of Series A Common Stock and 68,950,945 shares of Series B Common Stock.
• Mr. Bialecki also indirectly holds 7,517,410 Series B shares through the Andrew P. Bialecki Grantor Retained Annuity Trust I of 2023, 517,006 Series B shares through the Elizabeth L. Bialecki Irrevocable GST Trust of 2023, 517,006 Series B shares through the Andrew P. Bialecki Irrevocable GST Trust of 2023, and 43,218 Series B shares through his spouse.

Sentiment

Score: 5

Explanation: StockSavvy.ai views this as a neutral event. The sale was pre-planned under a Rule 10b5-1 trading plan, indicating a scheduled personal financial management action rather than a reaction to new company-specific information, thus having minimal impact on the company's fundamental sentiment.

Positives

• The transactions were executed under a Rule 10b5-1 trading plan, which indicates a pre-scheduled personal financial management action rather than a reaction to new material non-public information, promoting transparency and reducing concerns about opportunistic insider trading.

Negatives

• The sale by a Co-CEO, Director, and 10% owner, even if pre-planned, reduces their direct equity stake in the company, which some investors might perceive as a slight negative.

Risks

• No specific risks related to company operations or financial health were disclosed in this Form 4 filing, as it primarily reports insider transactions.

Future Outlook

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

Industry Context

StockSavvy.ai notes that insider sales executed under Rule 10b5-1 plans are a common practice for executives to manage personal finances, diversify their holdings, and address liquidity needs. These pre-arranged plans allow insiders to sell shares at predetermined times or prices without concerns of trading on material non-public information, thereby enhancing transparency and reducing potential market speculation compared to unscheduled sales.

Related Party Transactions

• Andrew P. Bialecki indirectly holds shares through the Andrew P. Bialecki Grantor Retained Annuity Trust I of 2023, of which he serves as trustee.
• Andrew P. Bialecki indirectly holds shares through the Elizabeth L. Bialecki Irrevocable GST Trust of 2023, of which he serves as a trustee.
• Andrew P. Bialecki indirectly holds shares through the Andrew P. Bialecki Irrevocable GST Trust of 2023, of which his spouse serves as a trustee.
• Andrew P. Bialecki indirectly holds shares through his spouse.

Stakeholder Impact

• Shareholders may note the reduction in the direct equity stake of a key executive, though the pre-planned nature of the sale under a 10b5-1 plan mitigates concerns about its implications for the company's future performance.

Key Dates

Recommendation

The Form 4 reports a pre-scheduled insider stock sale under a Rule 10b5-1 plan, which is a routine personal financial management event. This type of transaction does not typically signal a change in the company's fundamental outlook or warrant a shift in investment recommendation based solely on this filing. Therefore, a 'hold' recommendation is appropriate as this filing provides no new information to alter an existing investment thesis.

Keywords

Klaviyo, KVYO, Insider Trading, Form 4, Stock Sale, Andrew Bialecki, 10b5-1 Plan, Series A Common Stock, Series B Common Stock