If at first Prologis doesn’t succeed, it tries, tries, tries … and tries one last time.

The San Francisco-based industrial giant made what it described as a firm final preliminary offer to buy U.K.-based industrial developer Segro for more than $18.7B (£14B) on Wednesday, a $500M increase from its third rejected offer on Monday.

And this time, Segro recommended its board of directors take the offer if officially made, The Wall Street Journal reported.

The deal is one of the largest mergers ever of industrial REITs and comes in 14% above Segro’s estimated net asset value at the end of June.

News of the pending deal initially sent Prologis’ shares tumbling Thursday before rebounding midday, while Segro’s stock rose more than 7% on the London Stock Exchange. Already among the largest industrial development firms in the world, with some $240B in assets under management, Prologis’ acquisition of Segro would add 117M SF of European industrial and data center space valued at $29.3B (£22B).

Segro extended the deadline for Prologis’ formal offer, which also includes a partial cash alternative of up to $4.6B, until Aug. 12.

“The board of Segro has unanimously concluded that the financial terms of the fourth proposal are at a level that it would be minded to recommend to Segro shareholders,” the company said in a press statement to the WSJ.

Prologis said in a statement that a final deal isn’t guaranteed.

“Prologis' goal has always been a constructive process. The proposed combination represents a compelling opportunity for shareholders of both companies,” Prologis said in a press release. “Prologis welcomes the additional time afforded by the extension and is ready to work with the Segro Board in reaching an outcome that delivers value for all stakeholders.”

Segro’s board unanimously rejected three previous offers for acquisition by Prologis, beginning on June 24 with a $16.6B bid. Earlier this week, Prologis offered $18.2B, 9.7% higher than Segro’s estimated NAV.

Prologis argued that its ownership of Segro could accelerate the firm’s growth strategy, especially in the data center sector. But Segro countered that Prologis’ bids were opportunistic and that shareholders could benefit more with Segro as an independent company.

According to the WSJ, Prologis decided to raise its bid again after shareholder feedback. On July 21, Norges Bank Investment Management — which holds 1.3% of Prologis and 8.3% of Segro — encouraged the firms to come to “mutually beneficial terms” on a merger.

Prologis’ latest potential bid comes as the company raised its earnings guidance for 2026 after signing a record of more than 67M SF of leases, pushing occupancy up 20 basis points to 95.5%, the company reported in its earnings ending June 30. Prologis also broke ground on $1.6B in new logistics and data center projects as it rapidly ramps up its spec development pipeline.