The founding family of Italian luxury shoemaker Tod's said it was ditching a planned buyout of the group, after failing to reach the 90% ownership threshold needed to take it private.

Shares in Tod's plunged almost 20% on Wednesday to 31.9 euros, a level last seen before the Della Valle family's bid was announced at the start of August.

The offer's failure means the Della Valles must decide whether to proceed with the proposed de-listing of Tod's anyway, by merging the group into the family vehicle DeVa Finance - a possibility raised in the bid's documentation.

DeVa said in a statement late on Wednesday it was yet to decide whether to press ahead with the de-listing. A person close to the transaction said the family was expected to take a decision on the next step in the next couple of days.

Tod's founder and Chairman Diego Della Valle and his brother Andrea had offered to buy out other investors at 40 euros a share and de-listing the company via a merger with DeVa Finance would likely leave minority shareholders worse off.

Investors who oppose the merger would be able to exercise their withdrawal rights and liquidate their holdings, broker Equita said, calculating a price for that of 36.2 euros.

The Della Valle family owns 64.5% of Tod's, while another 10% is in the hands of France's LVMH, which supported the de-listing.

With the shares tendered under the bid, which will now be returned to investors, the Della Valles reached a stake of just under 87%.

The buyout bid was the latest attempt at revamping a company that, like other storied Italian brands, built its name on craftsmanship but now struggles to appeal to younger luxury shoppers.

The move aimed to manage the company's diverse brands separately, possibly divesting some to focus investments on the most profitable ones, Roger Vivier and Tod's.
That goal has not changed despite the offer not succeeding, the Della Valle family said.

"From tomorrow we will all work to achieve in the necessary timeframe the realisation of a project that we hope will be very successful," it said.In addition to the eponymous brand famous for its Gommino loafers, Tod's also owns the Fay and Hogan labels, as well as Roger Vivier, whose $800 a pair buckled shoes and successful relaunch have made it the group's crown jewel.