People do it to goof around all the time. I can buy nine hundred and eleven shares and it shows up as 911. It means nothing but people like to associate those trades with some sort of James Bond type code.
Think about it, if they really wanted to signal in code would they use such a basic code to do it?? The objective would be to send out a signal that other people viewing L2 would not understand. They aren't sending any signals, it's either people playing games, or just erroneous trades that mean nothing and people have chosen to assign this "code" to it.
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