PayPal announces support for buying, selling, and holding Bitcoin for its 346 million active users worldwide. While not self-custody -- users cannot withdraw BTC to their own wallets -- it marked a watershed moment for mainstream adoption. The same company that had banned early Bitcoin businesses was now embracing it. PayPal's announcement contributed to a rally that took Bitcoin from $12,000 in October to over $40,000 by January 2021.
Wikipedia: PayPal