The threat of a cashed up rival bidder – which some say may have been PayPal – spurred Square to strike its $39 billion deal with Afterpay early last month, a new regulatory filing by Jack Dorsey’s payments behemoth has revealed.

The filing reveals that it was a takeover offer from another “large, well-capitalised strategic party” in March that provided the catalyst for Square to jump on Afterpay and ride the surging interest in buy now, pay later instalment payments in the United States.