A consortium consisting of Blackstone, Carlyle and the Canada Pension Plan Investment Board has made a roughly 16 billion euro ($17.5 billion) bid for Thyssenkrupp's elevator unit, two people familiar with the matter said.
The bid is the highest among private equity suitors, who had until Tuesday to submit binding bids, the people said, adding no decision has been made on who has advanced to the final round of the auction.
Representatives for the consortium declined to comment.
Swiss elevator maker Schindler would embark on an all-out antitrust offensive in the courts to stall any deal to combine Thyssenkrupp's lift division with rival Kone, board member Alfred Schindler told Reuters.
His comments came a day after the deadline for binding bids for Thyssenkrupp Elevator, which Finland's Kone and three private equity consortia are looking to buy in a deal sources say could be worth up to 17 billion euros ($18.6 billion).
A combination of Kone and Thyssenkrupp Elevator would create the world's largest lift maker, leapfrogging the market leader Otis, which is owned by United Technologies', and Schindler, currently in second place globally.
"We would probably file lawsuits in Europe, the United States, Canada, China and possibly Australia. These cases would take at least three to four years," Schindler, who currently serves as the Swiss company's chairman emeritus, said.
He said he would expect other rivals to take legal action in the event of a sale to Kone: "You can safely assume that neither Otis nor Schindler will simply accept being driven out."
Thyssenkrupp declined to comment. Kone and Otis did not immediately respond to requests for comment.
Once a symbol of Germany's industrial power, Thyssenkrupp is struggling with 12.4 billion euros of debt and pension liabilities after years of ill-fated investments and needs to raise money from its prized elevator division.
Thyssenkrupp plans to make a decision on what it will do with the business by the end of February. Besides a full or partial sale, it is also pursuing plans for an initial public offering, though sources said this was becoming less likely.
While an outright sale to Kone would probably raise the most cash for the beleaguered conglomerate, Thyssenkrupp is concerned it might trigger antitrust investigations in a number of markets where the combined company could become a dominant player.
If Kone is selected, the deal is expected to result in lengthy antitrust reviews in Europe as well as the United States which could lead to the sale of some assets to rivals to secure regulatory approval.
Having served as the company's CEO from 1985 until 2011, Schindler's assessment carries significant weight, while the Schindler and Bonnard families, and parties related to them, hold 71.1% of the company's voting rights.
Schindler, who transformed the Swiss company into a global player, said besides legal steps, it would also intensify its operational efforts to fight any tie-up between the two rivals.
"There will be a technology war. It is already ongoing but it will intensify massively," Schindler said, without providing any specifics.
"Surprise lies at the heart of any defense strategy. A strategy that you lay out in advance would go against any rule of warfare."