MAI Basic Four Inc says it intends to top the $1,060m offer for Prime Computer Inc from J H Whitney & Co, and has filed suit in Delaware court alleging that Prime conspired with J H Whitney to conduct a rigged auction for the Natick minimaker, and demanding that Whitney be required to return the $20m paid to it by Prime in expense reimbursement fees before it is allowed to proceed with the bid; it is also demanding that Prime be ordered to give it confidential business information; Whitney says that such payements are normal in buyouts.