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Patents are granted for 20 years, but pharmaceutical companies cannot use their patent-guaranteed monopoly powers for anywhere near this long because it takes several years to acquire Food and Drug Adminstration (FDA) approval of drugs.

• What purposes do barriers to entry created by the government serve?
• What are other barriers to entry in the pharmaceutical industry?
• Should drug patents be extended to 20 years after FDA approval?
• Explain what would be the costs and benefits from this extension.