Duke Realty stock is soaring Tuesday after Prologis publicly announced a bid for the industrial real-estate investment trust firm.

Prologis (ticker: PLD) said it ticked up an all-stock offer on May 3 to 0.466 share for each Duke (DRE) share. On Nov. 29, Prologis, a REIT focused on logistics and warehouse properties, had offered 0.465 share per Duke share. But because Duke stock has been underperforming Prologis between the offer dates, the premium for Duke stock has changed to 29%—$61.68 a share—as of the close on May 9 from 20% in November. Duke, which is focused on industrial and medical-office properties, rejected the revised offer the same day.

Reiterating the offer in a public letter on Tuesday, Prologis said, "We are confident that the proposed combination will be a win-win for our respective shareholders."

Duke Realty's stock is up 10% in Tuesday morning trading to $52.66, while Prologis stock is down 1.2% to $130.78.