O 26 r 16 of the Rules of the Supreme Court 1971 (WA) permits variation of any order for discovery or inspection, including orders made by registrars, if sufficient cause is shown; the rule is not to be read down to operate merely as a slip rule. Parties operating at different levels of a supply chain (wholesaler and end-user purchaser) are not trade rivals merely because they may both obtain goods from the same manufacturer.
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