Linear polyethylenes with a combination of incorporated in-chain keto as well as side-chain ester groups are formed by Ni(II)-catalyzed terpolymerization of ethylene, carbon monoxide, and methyl acrylate. These possess a random structure, with largely isolated nonalternating in-chain keto groups as well as ester-substituted units adjacent to the polyethylene chain, whereas the solid-state structure of polyethylene is retained. Molecular weights of the terpolymers (Mn ∼ 20.000 g mol-1) are predominantly determined by chain transfer after acrylate incorporation.