Because John Stradwick, Jr., his brother W.L. Stradwick and H.D. McGilvery, who collectively owned more than 50% of the shares of Stradwick's and Vina-Rug, had at all material times a sufficient interconnection as to be in a position to exercise control over the two corporations, and therefore constituted a 'group of persons' within the meaning of s. 39(4) of the pre-1972 Act, the two corporations were associated. It was irrelevant whether other combinations of majority shareholders could be found.