An implantable vessel filter including an elongated body coupled proximally to a hub, and including a grooved distal section. A first set of legs coupled proximally to the hub have a first length, each of the first set of legs translating from a collapsed state in a filter compressed configuration to an extended state in a filter expanded configuration. A second set of legs coupled proximally to the hub have a second length longer than the first length, each of the second set of legs including a hook positioned at a distal end thereof, each of the second set of legs translating from a collapsed state in the filter compressed configuration to an extended state in the filter expanded configuration, each hook received in the grooved distal section in the filter compressed configuration and penetrating a wall of a vessel in the filter expanded configuration.