European car giants seen as safe bet

This year's 12 percent plunge in the euro has ignited the biggest rally on record in automakers and helped push the DAX Index above 12,000. Demand for ways to protect those gains is also soaring.

Options on BMW AG and Volkswagen AG are the most expensive in more than two years relative to those on the Euro Stoxx 50 Index, and contracts on Daimler AG climbed to their highest price since October 2013, data compiled by Bloomberg show. All three companies have rallied more than 36 percent this year.

Carmakers have become Europe's hottest stocks, partly because traders bet a weaker euro will translate into higher profits. But investors such as Dirk Thiels at KBC Asset Management say the advance may have gone too far, in part because currency hedges from companies will limit the benefit to earnings.