MCK vs AMT Comparison

McKesson Corp is one of three leading pharmaceutical wholesalers in the US engaged in sourcing and distributing branded, generic, and specialty pharmaceutical products to pharmacies (retail chains, independent, and mail order), hospitals networks, and healthcare providers. Along with Cencora and Cardinal Health, the three account for over 90% of the US pharmaceutical wholesale industry. Outside the US market, McKesson engages in pharmaceutical wholesale and distribution in Canada. Additionally, the company supplies medical-surgical products and equipment to healthcare facilities and provides a variety of technology solutions for pharmacies.

American Tower owns and operates about 150,000 wireless towers throughout the US, Asia, Latin America, Europe, and Africa. It also owns and/or operates 30 data centers in 11 US markets after acquiring CoreSite. The company's customer base in the tower business is very concentrated, with most revenue in each market generated by the top three or four mobile carriers. The company operates more than 40,000 towers in the US, which accounted for about half of total revenue in 2025. Outside the US, American Tower operates about 47,000 towers in Latin America (dominated by Brazil), 33,000 towers in Europe, and 28,000 towers in Africa. American Tower operates as a REIT.