A supplier group is powerful when:
• It is dominated by a few large companies and is more concentrated than the industry to which it sells.
• Satisfactory substitute products are not available to industry firms.
• Industry firms are not a significant customer for the supplier group.
• Suppliers’ goods are critical to buyers’ marketplace success.
• The effectiveness of suppliers’ products has created high switching costs for industry firms.
• It poses a credible threat to integrate forward into the buyers’ industry.