One has to look into the specifics of the case.But as a general rule..
For example, In a Government Tenders, two firms X and Y participate and :-
Case#1:- The MDs of X & Y are real brothers.
Case#2:- MDs of X & Y are real brothers but MD of X is a Director of Y or vice versa.
Case#3:-MDs of X & Y are the same but other Directors are different.
Case#4:- MDs of X & Y are not related but one of the Directors is common.
In the above scenario:-
> Case#1--Both the Firms are different and tenders from both the Firms will be considered.
>Case #2 ,3 &4- the firms will be treated as related and the Government has right to accept Tender from one Firm only to increase competition and to avoid cartelisation.