Given the task definition and input, reply with output. Indicate a text span in the passage about which an inquisitive question is asked. (note, don't answer the question).

Sentence: HOFI , the North American holding company of Swiss concern Holderbank Financiere Glaris Ltd . , previously proposed combining its 100 % stake in St . Lawrence Cement Inc . and its 60 % stake in Dundee Cement Co . with its 67 % stake in Ideal .<sep>Question: Why are they combining their stakes?
combining