Data are presented on the continuous-wave (cw) room-temperature (300 K) operation of multiple stripe Al(x)Ga(l-x)As-GaAs quantum well heterostructure (QWH) laser arrays defined with native oxide contact masking. Use of the native Al(x)Ga(l-x)As(chi-greater-than-or-similar-to 0.7) oxide allows the fabrication of high-performance devices without depositing foreign oxide or dielectric layers (SiO2 or Si3N4). Arrays of ten 5-mu-m-wide emitters on 7-mu-m centers are coupled and operate at powers as high as 300 mW per facet, or at wider stripe spacing (5-mu-m emitters on 10-mu-m centers) as high as 400 mW per facet. These data indicate that current blocking layers of native oxide, formed from Al(x)Ga(l-x)As with H2O vapor in N2 carrier gas (400-degrees-C, 3 h), can be used in the construction of high-power multiple stripe QWH arrays with excellent performance characteristics.