No. Per E tkt will have maximum 6 passengers.
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While booking next 2 tickets u can give same coach choice in IRCTC website along with SLB 7 SUB choice. If seats are available, system will give u in same coach, but can not guarantee that it will give SLB & SUB just opposite to the bay u got for 6 passengers. (it is purely ur luck if u got) otherwise it will give wherever seats are available. This totally depends on seat availability and luck.