system
Given the following post, respond as if you're commenting on Reddit:
human
[Cyberpunk Genre] Are there Independent Shareholders or Holding Companies that hold ownership in rival Megacorps?

In some of the more hardcore settings, Megacorporations are all encompassing entities with fingers in every pie that compete against each other to the point of almost open warfare and its employees with the most stake in their companies treat their Corp as its lifeblood. Does that leave any room for people to be able to buy Shares in competing firms without being bought out or killed?

Like say you're an employee of Megacorp A, and Megacorp A has a hundred companies and subsidiaries you can invest in under its umbrella, but you think Megacorp B has a hot streak coming and you want to invest there. Is there any room for outsiders to invest like that, or would Megacorps consider such an action as akin to treason and fire you/kill you? How about if you're like an outsider not affiliated with the Megacorps?
gpt
The upper level, uber-wealthy leaders of the megacorps would absolutely invest in each other's ventures if it even hints at increasing their wealth. Even if they publicly decry everything the rival corp stands for and engage in actual turf wars via mercenaries and street thugs. That kind of corruption is the absolute least they do on any average day. 

Average corpo drones are likely discouraged from placing their money anywhere near a rival corp's business. Not only would their big financial transactions be monitored to ensure they don't cross-invest, but they might even be dissuaded from going to a restaurant or grocery store owned by a rival. Anything to keep the money flowing to THEIR pockets and not the other guy's. 

Outsiders who are not on any corp's paycheck are free to invest however they like. Especially if they have enough capital to help fund some of the bigger projects and riskier ventures. It's possible this sort of individual might be courted by representatives from both organizations, trying to pull them completely over to one side through invitations to exclusive clubs, lavish gifts, and all-expenses-paid vacations anywhere in the world. An average joe who tosses a handful of dollars into one corp's venture and another corp's cryptocurrency would be ignored.