Which of the following do you think is correct (I've substituted real company names with X/Y/Z):
Competition Commission clears X's and Y's investment in Z.
Competition Commission clears X and Y's investment in Z.
In this scenario, X and Y are acquiring different percentage shareholdings.
I'd have thought the first sentence is better, for clarity, since it's possible to understand the meaning in the second sentence as "clears X" and "Y's investment in Z". On the other hand, "investment" is singular - a shared investment - although I wouldn't change to "investments".