The Compact Linear Collider (CLIC) is a future electron-positron collider that will allow measurement of the trilinear Higgs self-coupling in double Higgs boson events produced at its high-energy stages with collision energies of $sqrt{s}$ = 1.5 and 3 TeV. The sensitivity to the Higgs self-coupling is driven by the measurements of the cross section and the invariant mass distribution of the Higgs-boson pair in the W-boson fusion process, e$^+$e$^-to$HH$ u_e bar{ u}_e$. It is enhanced by including the cross-section measurement of ZHH production at 1.5 TeV. The expected sensitivity of CLIC for Higgs pair production through W-boson fusion is studied for the decay channels bbbb and bbWW using full detector simulation including all relevant backgrounds. With an integrated luminosity of $mathcal{L}$ = 5 ab$^{-1}$ at $sqrt{s}$ = 3 TeV, CLIC will be able to measure the trilinear Higgs self-coupling with a relative uncertainty of $-8,%$ and $+11,%$ at $68,%$ C.L., assuming the Standard Model.
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