Anti-competitive agreements: prohibited categories like price fixing and market allocation attract presumptions and voidness under competition law. Section 3 prohibits agreements that cause or are likely to cause an appreciable adverse effect on competition in India and declares them void. Competitor agreements fixing prices, limiting production or markets, allocating markets or customers, or causing bid rigging are presumed anti competitive, with a joint venture efficiency exception and an extended presumption for participants furthering the agreement. Vertical restraints such as tie in arrangements, exclusive dealing, exclusive distribution, refusal to deal and resale price maintenance are also prohibited if they appreciably harm competition. The section exempts protection of intellectual property rights and agreements solely concerning exports.