That's a problem of diversification, not conflict of interest.
Conflict of interest is something different.
For example: for the last few years I was doing a job that consisted of lowering my employee's profit. But at the same time my yearly bonus was based on the profit. In other words: I would be rewarded for bad work (or malpractice). That's a textbook example of conflict of interest.
As for conflict in investing: you're usually not allowed to be short on your company (because you would benefit from malpractice). I can't think of a better example.
I looked into this case during the last hour. IMO gathering funds for buyback is by far the most probable reason.
They most likely made this decision back in October when the stock was still high, but already started to go down after the mining bubble. Selling such a huge number of shares back then would be difficult. They secured the price with derivatives and waited. They sold the stock now - when it's cheap and it was easy to find buyers.
Again: diversification, not conflict of interest. They may have decided to lower their investment in this particular business.
But if that was true, they could have sold a part of ARM and keep some Nvidia.
In fact when you think about AI, it's almost necessary to invest in many companies - each one is working on a solution, so it's a competition (a race in fact).
If you believe that e.g. car AI will be hugely profitable in the future, you should buy shares of many (all) key players. This way you'll earn regardless of who wins the race.
But then you look at the share value and clearly the confidence is not shaken.
When a major investor announced selling AMD shares, they went down instantly. It's a different situation.
