I claim it is NOT ! I trade thin liquidity NYSE issues, and the price-improvement "algorithm" is running rampant these days. More than I have ever seen, and more than what the NYSE website claims (on the order of 40 % or so). This so-called "price improvement" that NYSE allows for, provides for penny (or more) improvements for those who are already willing to pay the "market" price for a stock, and causes "price disimprovement" for those that are posting limit orders, and are jumped in front of. This clearly disrupts the laws of supply and demand in the marketplace, and diminishes the usefulness of placing limit orders into the system. This results in diminished confidence in the marketplace by those placing limit orders, which will inevitably result in fewer limit order being placed. This will ultimately (and has already) diminished the liquidity in the marketplace, IMO. Why does someone who wants to buy at the market in the first place get a price improvement, while those who want to buy a t a limit price, continuously get price disimproved, via unfilled orders ? I just don't get this one........another "feature" of a totally antiquated market (NYSE). I truly believe that "price improvement" was devised by Grasso and company, in an attempt to rid the marketplace of Day Traders. What he is forgetting is that Day Traders contribute positively to liquidity, and Specialists are Day Traders, whose # 1 goal is to make money first; regulate the market 2nd (Grasso himself today said that his job of market regulation is only 1/3 of his job......). Enough said ! Comments appreciated.