Introduction 5. 2. The legal framework 8. 3. Incentives-based approach 12. 3.1. Innovation in existing product markets 12. 3.2. Innovation in future product markets 14. 3.3. Traditional theories of harm 16. 3.4. Remedies 19. 3.5. Challenges of the incentives-based approach 20. 4. Impact-based approach 22. 4.1. Innovation markets 23. 4.2. Innovation-specific theories of harm 25. 4.3. Remedies 33. 4.4. Challenges of the impact-based approach 34. 5. Inverse relationship: countervailing factors, efficiencies, and justifications 37. 5.1. Innovation as a counterbalance of market power 37. 5.2. Innovation as part of an efficiency claim 38. 5.3. Innovation as a justification.