On Thursday, Toyota Industries’ stock surged to an unprecedented peak following Toyota Motor’s decision to significantly increase its tender offer for the company by more than 15%, valuing the buyout at over $35 billion.

The shares of Toyota Industries climbed nearly 6%, reaching 19,080 yen, which exceeded the newly adjusted offer. This suggests that investors might anticipate an even more favorable proposal.

Meanwhile, Toyota Motor, recognized as the globe’s top carmaker by sales, saw its shares rise by more than 2%.

On Wednesday evening, Toyota Motor announced it had upped its buyout bid for the affiliated company to 18,800 yen ($118.11) per share, up from the 16,300 yen per share offer disclosed in June of the previous year, as part of its strategy to privatize the firm.

Last year, Toyota Motor had sought to acquire Japan’s largest corporate group for 4.7 trillion yen. The deal included 1 billion yen from chair Akio Toyoda, and Toyota Motor’s investment of about 700 billion yen in non-voting preferred shares.

In December, Toyota Industries said it had asked for a higher price, citing concerns that the deal’s chances of success were limited.

“While the revised offer represents an all-time high, it remains arguably light,” said Arun George, a global equity research analyst on SmartKarma.

It comes in below the middle of the valuation range set out by the independent adviser, suggesting the company may still be undervalued, he said.

Toyota Industries, which founded Toyota Motor, produces a range of products including forklifts, engines, electronic components, and stamping dies.

“I expect there to be some interesting fireworks on this deal. It is the biggest mis-priced takeover in Japan for quite a while. To be clear I expect activist action,” said Travis Lundy, an independent analyst, adding that he expects activists to demand a higher price or try to block the deal.

In its latest sales and production report, Toyota Motor’s global output slid 5.5% to 821,723 units in November, marking the first year-on-year decline in six months. Global sales also fell 2.2% year-on-year, with the company reporting that sales in China fell after the country scaled back on purchase subsidies in certain regions.

The automaker flagged a substantial hit from U.S. tariffs, projecting a 1.45 trillion yen (over $9 billion) impact for its financial year ending March.

Toyota Motor last November announced it would invest $912 million across U.S. manufacturing facilities in five Southern states, part of a broader plan to spend up to $10 billion in the U.S. by 2030.