Image source: Caesarstone Ltd. What happened Shares of Caesarstone Ltd. (NASDAQ: CSTE) jumped on Monday after Bloomberg reported that Israel's Tene Investment Funds Ltd. has agreed to buy 1 million shares of the company from Kibbutz Sdot Yam. At 3 p.m. EDT, the stock was up about 14%. So what Tene will pay $43.5 million for 1 million shares of Caesarstone, with an option to buy 2 million additional shares within five years, according to Bloomberg's sources. The deal gives Tene a nearly 3% stake in the company three years after it sold its previous position in Caesarstone. The deal also gives Tene voting control of the kibbutz's remaining stake and two seats on Caesarstone's board. Shares of Caesarstone tumbled last year after the company lowered its sales guidance, and the stock has yet to recover. Tene is paying $43.50 per share, well below the peak level of around $70 per share reached last year. CSTE data by YCharts. In an interview with Bloomberg, Tene senior managing partner Ariel Halperin spoke in broad terms: "The Tene team is very happy to be back at Caesarstone. We are looking forward to working together with the management, the board and the other shareholders to improve the performance of the company and to achieve significant growth in the future." Now what Caesarstone's revenue growth has slowed down in recent quarters, but the company still consistently produces high-single-digit or low-double-digit year-over-year growth. Investors should never buy or sell a stock simply because a private equity fund or another big-name investor does. But Tene's purchase is a vote of confidence in the company, and the market is now more optimistic that Caesarstone can improve its results. A secret billion-dollar stock opportunity The world's biggest tech company forgot to show you something, but a few Wall Street analysts and the Fool didn't miss a beat: There's a small company that's powering their brand-new gadgets and the coming revolution in technology. And we think its stock price has nearly unlimited room to run for early in-the-know investors! To be one of them, just click here.Timothy Green has no position in any stocks mentioned. The Motley Fool recommends Caesarstone. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.