Anchoring devices, anchoring systems for intervertebral implants, intervertebral implants, and instruments and methods for implanting implants are disclosed. In preferred configurations, these various objects share the feature of comprising or cooperating with an anchoring device having a body comprising at least one curved plate elongated along a longitudinal axis, designed to be inserted through a passage crossing at least a part of implant, in order to penetrate into at least one vertebral endplate and attach implant onto this vertebral endplate by means of at least one stop retaining the implant, characterized in that the body comprises at least one longitudinal rib on at least a part of at least one of its faces, said rib being designed to cooperate with a groove made in passage of implant. In some preferred configurations, anchoring device comprises withdrawal stops or latches, and/or means for withdrawing the anchor from an inserted position.