Form 4: Klaviyo CEO Bialecki Sells Shares, Gifts Millions in Stock

Klaviyo CEO Andrew Bialecki reported sales of over 230,000 Series A shares and a gift of 3.4 million Series A shares, all executed under a Rule 10b5-1 trading plan.

Summary

• Andrew Bialecki, CEO, Director, and 10% Owner of Klaviyo, Inc., reported multiple transactions involving the company's stock between December 9, 2025, and December 11, 2025.
• All reported transactions were executed pursuant to a Rule 10b5-1 trading plan adopted by Mr. Bialecki on May 20, 2025.
• On December 9, 2025, 131,362 shares of Series B Common Stock were converted into Series A Common Stock. Subsequently, 130,562 Series A shares were sold at a weighted average price of $29.42, and an additional 800 Series A shares were sold at a weighted average price of $28.84.
• On December 10, 2025, 82,223 shares of Series B Common Stock were converted into Series A Common Stock and then sold at a weighted average price of $30.12.
• On December 11, 2025, 17,777 shares of Series B Common Stock were converted into Series A Common Stock and then sold at a weighted average price of $30.00.
• Also on December 11, 2025, 3,419,000 shares of Series B Common Stock were converted into Series A Common Stock and subsequently transferred as a bona fide gift to a donor-advised fund.
• Following these transactions, Mr. Bialecki's direct beneficial ownership of Series B Common Stock decreased to 69,907,537 shares.
• Mr. Bialecki also holds indirect beneficial ownership of Series B Common Stock through various trusts and his spouse, totaling 8,084,640 shares.

Sentiment

Score: 5

Explanation: The filing reports routine insider transactions (sales and a gift) executed under a pre-arranged 10b5-1 plan. This is a neutral event as it reflects personal financial planning rather than a reaction to new company performance or outlook.

Positives

• The sales were executed under a pre-arranged Rule 10b5-1 trading plan, indicating a planned liquidity event rather than an immediate reaction to company performance.
• The gift of 3.419 million shares to a donor-advised fund demonstrates philanthropic activity by the CEO.

Negatives

• The sale of 231,362 Series A shares by the CEO, while planned, represents a reduction in direct ownership by a key insider.

Risks

• No specific company-related risks are detailed in this Form 4 filing beyond the inherent perception risk associated with insider stock sales, even when pre-planned.

Future Outlook

The filing details pre-scheduled transactions under a Rule 10b5-1 plan, indicating planned liquidity and philanthropic activities by the CEO. It does not provide forward-looking statements regarding the company's operational or financial performance.

Industry Context

This Form 4 filing reflects routine insider transactions, specifically sales and a gift, executed under a pre-arranged trading plan. Such transactions are common among executives for personal financial planning, diversification, and philanthropy, and do not inherently signal changes in the company's operational strategy or industry position. The market typically views 10b5-1 sales as less impactful than unscheduled sales.

Comparison to Industry Standards

• Not applicable. This filing reports insider trading activity, which is not typically compared to industry operational or financial benchmarks. The execution of sales under a Rule 10b5-1 plan is a standard practice for executives to manage personal stock holdings while avoiding accusations of trading on material non-public information.

Related Party Transactions

• The filing details indirect beneficial ownership through various trusts (The Andrew P. Bialecki Grantor Retained Annuity Trust I of 2023, The Elizabeth L. Bialecki Irrevocable GST Trust of 2023, The Andrew P. Bialecki Irrevocable GST Trust of 2023) where the reporting person or their spouse serves as a trustee, which are considered related party holdings.
• The gift of 3,419,000 shares to a donor-advised fund is a transaction involving the reporting person.

Stakeholder Impact

• Shareholders: The sale of shares by the CEO, while pre-planned, represents a reduction in direct insider ownership. However, the execution under a 10b5-1 plan mitigates concerns about immediate insider sentiment. The gift has no direct impact on other shareholders' holdings.
• Employees, Customers, Suppliers, Creditors: No direct impact on these stakeholders is indicated by this filing, as it pertains to personal stock transactions of an executive.

Next Steps

• The reporting person undertakes to provide full information regarding the number of shares sold at each separate price within the reported ranges upon request to the Issuer, security holders, or the SEC staff.

Key Dates

Recommendation

The filing details pre-scheduled insider sales and a significant gift by the CEO, executed under a Rule 10b5-1 plan. These are routine personal financial management activities and do not reflect new information about the company's operational performance or future prospects. Therefore, the filing itself does not provide a basis for a change in investment recommendation; a 'hold' stance is maintained pending further company-specific news or financial results.

Keywords

Klaviyo, KVYO, Andrew Bialecki, insider trading, Form 4, stock sale, stock gift, 10b5-1 plan, Series A Common Stock, Series B Common Stock, CEO, director, 10% owner