Is a gift won from a commercial bank, as a result of a draw on coupons distributed to the public attending an event organized by the bank, permissible or forbidden (halal or haram)?

Accepting a pure gift from a usurious bank is permissible, though disliked. However, attending a ceremony held by the bank for promotional purposes or to announce winners of a draw on usurious transactions is not permissible. In such a case, accepting a gift offered at such a ceremony is also not permissible.