AmerisourceBergen is a drug distributor / wholesaler, so they have huge revenues bc they sell expensive drugs, but they don't capture much of that (their net income is negative)
Express scripts is a PBM and highly profitable. I don't really know what PBMs do at a useful level of detail, but their profitability has been a subject of debate as pharma companies blame them for high prices. They basically aggregate demand for drugs and negotiate prices on behalf of payers, and make money on their ability to do so
Gilead had one of the best selling drugs of all time, that did $5B in revenue in the first quarter of launch, and $20B+ in the first year I think. Since then rev has declined but still massive
The insurance companies get lots of rev from premiums but margins are low
Biogen and celgene also have one or two drugs that do $5-10B / year
Should note that drugs only account for 10% of health spend. The biggest driver of healthcare costs -- hospital care (30%) and physician services (20%) don't show up in this chart bc they are fragmented industries and also human-capital intensive
Were you in a class with Professor Long at Tulane? He has a great, great slide illustrating these and many other facts about the US healthcare economy over the last century.
Definetely needs to be weighted.
An example, Murphy Oil Corporation has 1,294 employees...
Also another interesting trend is how many healthcare companies are in that list.