What are the advantages and disadvantages of a company integrating another company vs leaving it as an independent entity?

I'm not sure his this works so I may be incorrect.

If Microsoft was to buy Samsung (highly improbable) what would be the difference, benefit and disadvantages of

Integrating it as a subsidiary thus removing it from the stock market and absorbing everything Samsung owns

Leaving them as a publicly traded company and giving them a high degree of autonomy but still taking most of their profits.

Note I'm talking about a wholly owned subsidiary in the first example (because i don't think the second option could be a wholly owned subsidiary and remain publicly traded, but if it could then compare it as wholly owned)