Not sure if this is still possible, but back in the days brokers kept suckers clients in a separate book, and didn’t bother to actually enter their trades in the market.
Back in the '80s, as most here know, I was programming in dBase (Borland) and FoxBase (later Foxpro) etc. In the insurance business, they kept a separate file for people who will NOT cause legal problems if you deny their medical claims, and in the natural medicine business (mail-order), they kept a list of people who were suckers! Meaning you can ship them anything, bill their credit cards, and they would NOT do a chargeback
PS. I was ONLY a "computer guy". I was in a foreign country (USA) with a student visa, getting paid by Engineering university professors to write code...and I did NOT have a work permit
. Did I mention my family was dirt poor? I knew it was wrong, but it was either that or trying my luck in the jungle...besides... the brother of my employer, the insurance guy, was my general advisor (not academic advisor) and the general advisor was an alumnus at my uni and he was the sitting US Attorney for that district (main prosecutor)... needless to say...I was so f*cked if I blew that whistle
- I am dumb as a rock, but NOT suicidal!