Shortly after the limit order display rule was implemented one of my Nasdaq orders failed to fill even though shares executed through my price. I was told that block orders are not subject to the limit order display rule. Ever since I have routinely split block orders into multiple orders at prices varying by one or two ticks for both Nasdaq and NYSE stocks. But I am woefully ignorant of how block orders are handled on either exchange. Because of the limit order display rule, it has always struck me that block orders are a bad idea, to be avoided whenever possible. I was wondering if anyone could point me to a discussion of block trades. How are they handled differently from non-block trades? Advantages? Disadvantages? How does their treatment vary by exchange? If there is no good source of information on block trades then perhaps we can use this thread to discuss them. The one difference I am reasonably certain of is, as I mentioned earlier, that Nasdaq block trades are not subject to the limit order display rule. I looked this up several years ago.