Maleic anhydride-stearyl methacrylate copolymer was synthesized by radical polymerization. The copolymer was fractionated and characterized by dynamic and static light scattering (DLS and SLS) experiments in different concentration regimes. Seven fractions of low polydispersity index (<1.18) were studied. A typical behavior corresponding to good and theta () solvents, according to the classical theories for polymers in solution, was found in the dilute regime. The results indicate in a semiquantitative way that this copolymer shows a normal behavior in the dilute regime. The rigidity parameters σ and C∞ show flexibility of the polymer chain, due to the incorporation of the maleic anhydride (MA) units, when the copolymer is compared with those corresponding to other poly(methacrylates) previously reported. In the semidilute regime and depending on the solvent nature, aggregation of the copolymer was detected. The aggregation was analyzed in terms of the values of the autocorrelation function determined by dynamic light scattering.