In a previous life I was in technology sales and when things were quiet, store staff literally went back through the last six month's worth of customers and called them up - how's it going, do you like your xyz, do you know anyone who might be interested, can we have their number?
MECO ("Maximising Every Customer Opportunity") files. It worked in the 90s and got us over the line every month. Now? I doubt it.
Someone at altium is doing the modern-day equivalent of that.