** Shares of Birkenstock BIRK.N up as much as 17% at $38.88

** Shares set for their best day on record since listing in 2023

** Co enters into a $250 million accelerated share repurchase program with Goldman Sachs

** Under the agreement, co to make a payment of $250 million to Goldman Sachs and expects to receive an initial delivery of about 6 million shares

** Co last week missed sales and profit estimates and warned of rising second-half cost pressures from U.S. tariffs and the Middle East conflict

** Accelerated share repurchase is expected to be completed before June 30

** Including session moves, shares down 5.2% YTD