Yes, quite a block.

Either 1) someone is stupid and greedy - making it hard to get their own price by dropping such a lump on the market, or

2) National (let's say they are market maker) is squashing the market to fill their boots, or the boots of europeans.

I figure #1 - the one big ask doesn't look like typical manipulation. What a bonehead the seller is, even if they think it's fair value. They are biting their own tail.