This banknote liability arises largely because the bulk of the euro currency circulating outside the eurozone is sourced from, and paid for in, Germany, meaning that the Bundesbank holds a much greater share of refinancing loan assets backing the euro banknote circulation than its statutory allocation.

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But the liability is far less than speculated in the market, with rumors circulating that the group's investment arm was nursing a much larger black hole in its finances.

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