Despite the ongoing travel restrictions and lockdowns upending the art market, auction houses are still rolling out masterpieces with some jaw-dropping prices.

The latest is Sotheby’s announcement today that it will offer a monumental Alberto Giacometti sculpture, the nine-foot-tall Grande Femme I, cast in 1960. The rare sculpture also comes with a rare bidding strategy, a sealed and confidential “Best Bid” system, under which “qualified participants” can submit bids starting today—as long as they offer a minimum of $90 million.

Cosmetics billionaire Ron Perelman is selling the sculpture, according to Bloomberg, part of a larger offloading of his 1,000-work collection in recent months. Sotheby’s declined to comment on the seller’s identity.

All offers received by noon on October 27 will be reviewed by Sotheby’s general counsel and an outside auditor. The highest bidder will win the work.

Sotheby’s says the sculpture is one of the most important Giacometti works to appear on the market since the record-setting L’homme au doigt (1947) sold for a record $141.3 million in 2015.

“We found recently, particularly through the shutdown, that the art market is a lot more flexible than people have assumed,” Brooke Lampley, vice chairman of Sotheby’s fine arts division, told Artnet News. “And we thought that such a special work merited a bespoke presentation. This is a way to embrace its worldwide appeal but also maintain the privacy and discretion that people often desire when bidding at this level.”

Lampley confirmed that there is no guarantee on the work. There is, however, a reserve, the undisclosed minimum at which the work can sell in the event that bids don’t far surpass $90 million.

“We haven’t really modeled it on previous sales,” said Lampley. “There have of course been sealed bid sales in the past but we thought carefully to structure this and design the process in the most beneficial way to the consignor.”

Lampley added that while she will speak to clients about their bidding strategy, “I will have no insight into what other clients are doing.” She will also not see any of the bids, which will go directly to the general counsel and auditor. “It really is about maximizing interest for the consignor and fairness for the buyer,” she added.

A Sotheby’s spokesperson explained that offers received that are within five percent of the value of each other will go to a further round of best bid offers, until a winning offer stands alone. Full rules and regulations about the event will be posted on the sale page when it goes live today.

Grande femme I is one of a series of four monumental female figures, each standing approximately nine feet tall, which the artist created for an outdoor sculpture installation in Chase Manhattan Plaza. The installation was never completed, but the series became iconic in their own right, and have been widely exhibited both independently and as an ensemble since their conception in 1960, according to Sotheby’s.

“The figure’s haunting, elongated form, immobilized by large feet that are firmly rooted to their base, towers over the viewer with the permanence and fortitude of a giant tree,” according to a statement from Sotheby’s.

In 1956, Gordon Bunshaft, the architect for the Chase Manhattan Bank building in New York City’s financial district, asked Giacometti to design a group of sculptures for the building’s plaza on Pine Street. Initially, Bunshaft had envisioned an enlarged version of Giacometti’s Three Walking Men of 1949. Instead, Giacometti proposed an entirely new composition that would be tailored to the proportions of the space. It would consist of a head on a pedestal, a walking man, and a standing woman. However, he never submitted his final versions of the sculptures to the selection committee in New York.

Giacometti had never visited New York City at the time of their conception and he had mixed feelings about the size of the Femmes, which he felt were too tall in their context with the building. But, when he finally visited New York in 1965 and saw Chase Manhattan Plaza for the first time, his feelings about the size of his sculptures abruptly changed, and he even proposed making his Grandes femmes 25-feet tall. Giacometti died before he could ever complete the work.

Grande Femme I will be on view at Sotheby’s New York galleries by appointment from October 21 to 27.