Sigma today has confirmed that in addition to being available in the Sigma, Nikon, and Canon mounts, the new Sigma 35mm F1.4 DG HSM A1 lens will also be coming for Sony and Pentax! This is a full-frame lens that's part of Sigma's new "Art" lens series for professionals.
This lens will be a fine addition to the Pentax K-mount lens lineup, as Pentax themselves offer no such lens (the SMC Pentax-M 35mm F1.4 prototype never ended up being mass-produced). The current non-macro Pentax 35mm lens is a comsumer-grade DA 35mm F2.4; the previous full-frame FA 35mm F2 is being phased out.
Through this lens, Sigma promises to deliver the highest in image quality and durability. All components used to make this lens will be extra-durable and resistant to changes in ambient temperature (thanks to Sigma's Thermally Stable Composites) in order to allow for prolonged and daily use. The lens has 9 rounded aperture blades for smooth bokeh and has 13 optical elements in 11 groups.