Check out this Q&A on Advertising in Hong Kong by Eugene Low and Charmaine Kwong from Hogan Lovells which considers:

• the framework regulating the advertising industry; the rules and standards required for substantiating advertising claims and for making disclosures;
• whether freedom of speech/expression rights affect the regulation of advertising;
• the complaints procedure; regulations on advertising methods (such as product placement, native advertising, subliminal advertising, outdoor advertising, and bait advertising);
• regulations on advertising content (including rules on false and misleading advertising, comparative advertising, testimonials and endorsements, and whether ads can create a contract between the advertiser and buyer of the product advertised);
• industry-specific regulations;
• restrictions on advertising to children;
• intellectual property right protections; and
• protections on the use of people in advertisements.