This month marks the 30th birthday of the SPDR S&P 500 ETF Trust (SPY), the granddaddy ETF that started it all and is still the largest and most-traded ETF in the world. But getting this ETF launched was no small task; neither was getting assets into it. Though once people saw its value-add, the financial world changed forever.

This week, we speak with Jay Baker, who — as vice president of options marketing at the American Stock Exchange — worked with Nate Most and Steve Bloom to drum up interest for SPY in the early ‘90s. We discuss where the idea for SPY came from, who the early investors were and what caused the tipping point, as well as the unique dynamic between Most and Bloom. We also look at whether SPY can hold onto its biggest-in-world status for much longer.