Extent of Malaysian waters off East Johor In nearly all the cases Gard has handled, mariners had mistakenly understood their anchoring position to be outside Malaysian territorial waters. As our correspondent, Spica, reports in their recent circular these waters are sometimes referred to as Singapore OPL East, or sometimes even International waters. The Merchant Shipping Ordinance 1952 and the Federation Light Dues Act 1953 All the recent detentions have been under section 491B(1) of the Malaysian Merchant Shipping Ordinance 1952 (MSO). This section stipulates that ships must notify the Director of Marine of activities within Malaysian waters whenever engaging in various activities. The relevant provision in this section under which vessels have been detained by the MMEA is 491B(1)(l) which is a sweep-up provision, requiring approval be obtained for “any other activity as determined by the Director of Marine”. The provision is widely worded, which makes it difficult to challenge.