The initial conversion price was set at about $22.72 per Class A share, i.e. a 30% premium over Monday's closing price. The notes, which bear annual interest of 1.75%, will mature on March 1, 2031, unless repurchased, redeemed or converted earlier. The structure enables Elliott to earn bond-like returns while retaining the option to convert into shares.

The proceeds will be used to fund a new $3.5bn share repurchase program authorized by the board. Pinterest also said it plans to buy back up to an additional $500m of stock using its available cash.

Following this announcement, Nasdaq-listed Pinterest shares are up over 6% on Tuesday.