Klaviyo, Inc. SEC Filings

A company officer completed multiple open-market transactions under a Rule 10b5-1 plan on 10/10/2025. The reporting person, the Chief Financial Officer, acquired 15,000 shares of Series B common stock and sold a total of 15,000 shares of Series A common stock in two blocks: 9,808 shares at a weighted-average price of $25.33 and 5,192 shares at a weighted-average price of $24.45. After these transactions the officer reports beneficial ownership of 481,719 shares of Series A common stock (including 439,032 unvested RSUs) and beneficial ownership of 393,476 derivative-linked shares (including 209,101 Series B shares and 184,375 unvested RSUs).

The filing discloses the trades were made pursuant to a 10b5-1 trading plan adopted on 8/16/2024, and notes that each Series B share converts into one Series A share. The reporting person signed the form via attorney-in-fact on 10/10/2025.

Andrew Bialecki, Klaviyo CEO, reported transactions under a Rule 10b5-1 trading plan executed on 10/07/2025. The report shows a conversion of 159,508 shares of Series B into Series A common stock followed by sales of those shares in multiple transactions at weighted average prices in the <$25.07–$25.32> range. After the reported sales, the filing indicates 0 direct shares beneficially owned by the reporting person.

The filing lists additional indirect holdings via trusts and spouse-controlled accounts totaling 8,594,640 Series A-equivalent shares across several trust and spouse relationships, with explicit disclaimers about Section 16 beneficial ownership limits. The transactions were effected pursuant to a 10b5-1 plan adopted on 5/20/2025.

Andrew Bialecki, Klaviyo CEO and director, reported insider transactions on 09/30/2025 under a Rule 10b5-1 plan adopted 05/20/2025. He received 137,224 shares of Series B common stock that are convertible into 137,224 shares of Series A common stock, and sold the full position in multiple block sales on the same date. The sales occurred at weighted-average prices disclosed in ranges from $27.68 to $31.77, with individual weighted-average sale prices reported as $31.24, $30.28, $29.03, $28.22, and $27.70. After these transactions the reporting person’s direct beneficial ownership of Series A common stock is 0. The Form 4 lists additional indirect holdings by trusts for which the reporting person is trustee, with specific trust-held share amounts disclosed.

Andrew Bialecki, CEO and director of Klaviyo, Inc. (KVYO), reported transactions dated 09/23/2025. The filing notes the acquisition of 211,358 shares of Series A Common Stock pursuant to conversion of Series B Common Stock and the sale of 181,553 shares at a weighted average price of $35.52 (sales priced between $35.025 and $36.02) plus an additional sale of 29,805 shares at a weighted average price of $35.01 (sales priced between $35.00 and $35.02). The transactions were effected under a Rule 10b5-1 trading plan adopted May 20, 2025. Footnotes identify several trust holdings for which the reporting person disclaims beneficial ownership except to the extent of pecuniary interest.

Insider transactions by Klaviyo director and 10% owner Ed Hallen on 09/15/2025: The filing reports multiple sales and a gift under a Rule 10b5-1 plan adopted June 12, 2025. Mr. Hallen sold 22,224 shares of Series A common stock from direct holdings at a weighted-average $31.65 per share and 67,524 shares from holdings attributed to Hodgkins Trust at a weighted-average $31.73 per share, with sale prices in reported ranges. He also made a bona fide gift of 20,260 shares to a donor-advised fund. After these transactions, beneficial ownership reported is 702,216 shares (indirect) via Hodgkins LLC and related entities.

Andrew Bialecki, Klaviyo, Inc. Chief Executive Officer and a >10% owner, reported transactions in the company’s common stock executed under a Rule 10b5-1 trading plan. On 09/16/2025 the reporting person converted 226,382 shares of Series B common stock into Series A common stock and sold a total of 226,382 Series A shares in two blocks: 140,921 shares at a weighted average price of $32.71 and 85,461 shares at a weighted average price of $31.76. The Form 4 lists various indirect holdings through trusts and shows transfers and ownership details for those trusts. The filing was submitted by an attorney-in-fact.

Luciano Fernandez Gomez, Interim Executive Officer and director of Klaviyo, Inc. (KVYO) reported a securities transaction dated 09/15/2025. The filing shows an award of 100,597 restricted stock units (RSUs) under the issuer's 2023 Stock Option and Incentive Plan, recorded as an acquisition at $0. The RSUs vest in full on November 15, 2025, subject to continued service. After the reported transaction the reporting person beneficially owns 127,385 shares equivalent, consisting of 20,968 shares of Series A Common Stock and 106,417 unvested RSUs. The Form 4 was submitted via attorney-in-fact Landon Edmond and signed on 09/17/2025.

Stephen Eric Rowland, President and officer of Klaviyo, Inc. (KVYO), reported voluntary sales of Series A common stock on 09/15/2025 under a Rule 10b5-1 trading plan adopted on 11/22/2024. The filing shows two disposal entries: 6,905 shares sold at a weighted-average price of $31.90 per share (transactions ranged $31.43–$32.27), and 200 shares sold at $31.24. After these sales the reported beneficial ownership is shown as 438,821 and 438,621 shares respectively. The filing discloses that the total reported holdings consist of 129,070 issued shares and 309,551 unvested restricted stock units convertible into common shares upon vesting.