As far as you know, these predictions could be used to make currency trades, or stock predictions, or real estate purchase, or something more exotic. You really have no idea. And since you don't know what these data points represent you can't use any insider knowledge about anything to help you.
only 1 or at most a few of those 21 features represent real data. The real data represents similar information to the insider information which they wish to act upon.
Example data prep:
1. Insider source says that a contract is falling through, a patent is being filed for, quarterly numbers have been missed/surpassed etc.
2. Similar information is gathered from historic performance data of the company, similar companies or market segments.
3. The information is correlated with whatever metric they wish to move along and encoded in one of the 21 feature classes.
4. Repeat for whatever relevant information that can be linked to the insider source - i.e. competing companies, re-encoding separately for long and short positions etc.
5. Fill in remainder of 21 feature classes with noise.
Inside traders are usually caught because they make profitable trades shortly before significant company events, or they're caught communicating with the tipper. This wouldn't protect from that.
Once they're being investigated having a plausible reason for making the trade is mostly irrelevant. If you have no reason other than inside information for trading and just say "I felt like gambling" it doesn't matter. If they can't actually prove you had the inside information you're innocent.
If they can prove you had illegal inside information it doesn't matter if you can prove that you made the trade for unrelated reasons. You're guilty.
So you get your tip, and you generate a data set that will result in some data analyst getting the conclusion you want.
Half of 42.