An apparatus for forming a flexible package, comprising: a forming box having a first end and an oppositely disposed second end, wherein the forming box comprises first, second, and third portions (14, 16, 18) that cooperate to define first, second, third, and fourth walls of the forming box, each extending between the first and second ends, the first and second ends of the first portion defining first and second mating surfaces (40, 42) of the first portion, and the second and third portions (16, 18) each comprising a third and fourth mating surfaces (52, 64), respectively; one or more forming box actuators operatively coupled to one or more of the first, second, and third portions (14, 16, 18) of the forming box and configured to actuate the forming box between a first position for receiving a package, a second position for retaining a package, and a third position for releasing the package, wherein in the first position, forming box is actuated such that the first, second and third portions (16, 18) are separated to allow the package to be received within the forming box but prevent the package from passing through the forming box, in the second position, the forming box is actuated to close the first, second, and third portions (14, 16, 18) with the third and fourth mating surfaces (52, 64) of the second and third portions (16, 18), respectively, in contact or substantially in contact with a respective one of the first and second mating surface of the first portion, such that a first surface of the first portion and the mating surfaces (40, 42, 52, 64) define a wall of the forming box to retain the package, and in the third position the forming box is actuated to separate the first, second, and third portions (14, 16, 18) to allow the package to exit the forming box; a first flap folding bar disposed upstream and adjacent the first end of the forming box, wherein the package is received in the forming box such that a wall of the package located at the first end of the forming box has a seal extending perpendicularly or substantially perpendicularly from the wall; and one or more first flap folding bar actuators operatively coupled to the first flap folding bar and configured to actuate the first flap folding bar in a direction substantially transverse to a transport path of a flexible material between a first position in which the first flap folding bar is disposed away from the forming box and a second position in which at least a portion of the first flap folding bar is disposed over the first end of the forming box. a forming box having a first end and an oppositely disposed second end, wherein the forming box comprises first, second, and third portions (14, 16, 18) that cooperate to define first, second, third, and fourth walls of the forming box, each extending between the first and second ends, the first and second ends of the first portion defining first and second mating surfaces (40, 42) of the first portion, and the second and third portions (16, 18) each comprising a third and fourth mating surfaces (52, 64), respectively; one or more forming box actuators operatively coupled to one or more of the first, second, and third portions (14, 16, 18) of the forming box and configured to actuate the forming box between a first position for receiving a package, a second position for retaining a package, and a third position for releasing the package, wherein in the first position, forming box is actuated such that the first, second and third portions (16, 18) are separated to allow the package to be received within the forming box but prevent the package from passing through the forming box, in the second position, the forming box is actuated to close the first, second, and third portions (14, 16, 18) with the third and fourth mating surfaces (52, 64) of the second and third portions (16, 18), respectively, in contact or substantially in contact with a respective one of the first and second mating surface of the first portion, such that a first surface of the first portion and the mating surfaces (40, 42, 52, 64) define a wall of the forming box to retain the package, and in the third position the forming box is actuated to separate the first, second, and third portions (14, 16, 18) to allow the package to exit the forming box; a first flap folding bar disposed upstream and adjacent the first end of the forming box, wherein the package is received in the forming box such that a wall of the package located at the first end of the forming box has a seal extending perpendicularly or substantially perpendicularly from the wall; and one or more first flap folding bar actuators operatively coupled to the first flap folding bar and configured to actuate the first flap folding bar in a direction substantially transverse to a transport path of a flexible material between a first position in which the first flap folding bar is disposed away from the forming box and a second position in which at least a portion of the first flap folding bar is disposed over the first end of the forming box.