Buybacks were illegal throughout most of the 20th century because they were considered a form of stock market manipulation. But in 1982, the Securities and Exchange Commission passed rule 10b-18, which created a legal process for buybacks and opened the floodgates for companies to start repurchasing their stock en masse.”
https://www.zerohedge.com/news/2019-04-14/make-stock-buybacks-illegal
