[pdovy]

Yeah this seems like a baseless claim to me. I work on these kinds of applications and we always assume that an order is eligible to execute from when it's sent until the exchange confirms it has been canceled/deleted. This is pretty standard and it's surprising that a big bank would have such an obvious hole in their risk system, and disappointing that they would then fail to take responsibility for their own mistake.

[cube13]

I think the standard IPO buying strategy for a large institution like UBS is to make many large buy requests to make absolutely sure that all the brokers that want stock get it, then cancel when enough orders are fulfilled.

Since interest was very high on the FB IPO, the assumption would be that it would be fairly hard to actually get stock. So the bank would make a lot of requests, on the hope that a certain percentage would be fulfilled immediately(say 30-40%), after which they could cancel the remaining orders.

Unfortunately, this turned out not to be the case, because a LOT of FB stock was released to the market. Add to that that NASDAQ(as UBS contends) did not give a confirmation ID to UBS, and it's pretty easy to see why this happened.