" Information on short selling activities is  relevant to the trading decisions of market participants. For example, information that those securities are under sustained heavy short selling may indicate strong negative price pressure on those securities.

As such, disclosure of short selling activities in Singapore is a step towards  enhancing the information available for traders and investors to make informed trading decisions.

Information on short sale transactions also helps to  deter market abuse  by alerting authorities to activities that may potentially disrupt the orderly functioning of markets, and aids in investigation and enforcement.

Market participants should exercise care when interpreting information on short selling. For instance, information on short sale volume may not reflect the outstanding short position in those securities. Volume of short sales may include trades which have since been squared off by offsetting buy trades.  "

  2. Intepretation is of value, like the one in point 1. Anyway, this report is nothing new in the industry. US has it for long time, http://www.sec.gov/answers/shortsalevolume.htm SGX is kinda lagging behind.

3. Exemptions are given to market makers as they may have activities like managing liquidity, derivatives, and hedging. Regulators are not so keen about these " regular" activities these banks/fund managers do, but by speculators who will bring sudden instability to the market. Anyway, more details on the rules http://rulebook.sgx.com/net_file_store/new_rulebooks/s/g/SGX-ST_Mar_11_2013.pdf

SGX may have more answers to the questions you still have:  http://www.sgx.com/wps/portal/sgxweb/home/faqs#Marking_of_SellOrders