[trogdor]

If a company has a specific knowledge advantage regarding the design or manufacture of turbine blades, wouldn’t they patent it?

[applied_heat]

Patents expire

Patents are difficult to enforce internationally

Where would coke be if the recipe was patented instead of trade secret ?

[chii]

While your point is completely true, the specific example of coke is ironic because Coke's dominance is more related to marketing than their formula!