tt+X and 4-top quarks

Analyses of the production of a top-quark-antiquark pair in association with a vector boson and of four-top-quarks are presented. The measurements use √s=13 TeV proton-proton collision data collected by the ATLAS detector and the CMS detector at the Large Hadron Collider. Inclusive and differential cross-section measurements are shown. The talk focuses on the evidence of the four-top-quark production which is supported by the latest combination. Interpretations using effective field theories and models for new physics are also reported.