Square has introduced Bitcoin as a payment option for merchants, coinciding with a 10% rise in Block's stock following its inclusion in the S&P 500. Block's CEO, Owen Jennings, announced the onboarding of initial Square sellers for Bitcoin payments, a move aimed at enhancing accessibility. The company, founded by Jack Dorsey, initially revealed plans for BTC payments in May, focusing on ease of use via QR codes. Block's stock is currently trading at $79.50, up from $66 on July 15th.