Odd lots now make up a very large share of US trade count, driven by high share prices and retail activity. They are reported to the consolidated tape as trades, so they appear in volume and in time-and-sales, but odd-lot orders alone do not set the national best bid and offer.
The consequence for reading a tape is that a stock can print many small trades at prices inside the displayed quote. That is not an error; it is odd-lot interest that the quote never showed.
Example: a trader buys 37 shares of a $2,400 stock, an $88,800 order that is technically an odd lot. Meanwhile the displayed quote reflects the 100-share interest of far smaller dollar value.
Related: round-lot, mixed-lot, fractional-shares, time-and-sales, bid-ask-spread