80% of their customers were car battery companies, and I think Johnson? makes most car batteries in america (under different brands). Ammunition is the other big customer.
I consulted in IT for ~10 years, and tried to take interesting jobs in interesting industries, after burning out in big healthcare. One of the more interesting gigs I took was working for a lead smelter!
They smelted all their lead from recycled materials, mostly batteries. That is why you get a relatively lot of money back for your used battery. They have ~15 customers and a LINE of more waiting if they could support the capacity.
Looks like an interesting article, with complex problems and solutions. My problem is I have no idea what a "rotating bloom filter" would be used for in a real-world system.
...and he details how the Wall Street Journal was pressured by very powerful people / organizations and they fully stood by their journalists. Very surprising and encouraging.