Many will watch level 2 to see what market makers are on the ask. Certain market makers are notorious for being used mostly for dilution. Top Retail Dilutors : ACAP, AGIS, BAMM, BMAK, BMIC, CHIG, CLYP, FANC, FRAN, JIMK, MAYF, NATL, PERT, SACM, UCAP, VERT, VFIN. Other market makers, like NITE, are very large and cater to both retail investors and companies looking to dilute. A very low share count by a market maker on the ask that never seems to fill is about the best indicator you could spot.
The Accumulation/Distribution (A/d) line can also be used to spot longer term dilution. The A/d line typically mirrors the price of the stock, like this chart. http://i.imgur.com/PoNI8Kv.png When the price is decreasing or steady, but the a/d line is increasing, this signals that there is an increase in the amount of sellers but not buyers, like this chart http://i.imgur.com/wyZm2BL.png. This can be one way to signal if you are dealing with dulution. You can see the dilution started late last year and that people who have no clue about this indicator are stupidly buying it by the truck load but the price stays almost completely flat. This is because despite the extra buyers, there is still plenty of supply because of dilution. The company is issuing new shares in to the face of the oncoming buyers and pocketing the money.
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