Klaviyo Inc. (KVYO) stock plummeted 10.4% in the pre-market session on Thursday, following the company's mixed fourth-quarter earnings report and the announcement of pricing changes that could lead to customer churn.

While the marketing automation platform reported a 34% year-over-year increase in revenue to $270.2 million for Q4 2024, surpassing analysts' expectations, its adjusted earnings per share of $0.07 fell short of the forecasted $0.12. The revenue upside was driven by strong performance in the mid-market and enterprise segments, as well as robust international growth.

However, investors appeared concerned about the company's weaker-than-expected earnings and the potential impact of a planned stock offering by certain selling stockholders. Additionally, Klaviyo announced pricing changes effective from February 19th, including the enforcement of pricing based on active profiles and the introduction of auto-downgrades and flexible sending options for email and SMS.