That depends on what you mean by "cut", but the quick answer is "None, necessarily".

However, the detailed answer is: Because the self tacking jib has to fit inside the triangle defined by the forestay and mast, it is typically smaller than jibs that are not self tackers. In order to max out the available size (which is commonly desired and attempted), it is usual to cut the leech longer and bring it as close to the block(s) on the self tacker track as possible. This means that the sheeting angle is almost directly up the leech when the sheet is pulled tight and it requires having the best trim angle accurately located in the design. On older boats that have ovelapping jibs, like the Hobie 18, the clew is cut higher, the sheeting angle is almost into the middle of the sail, and there is a track allowing for fore and aft adjustment for best trim to account for differences in how the sail was designed or cut and also for close reaching or for different trim in different wind speeds and/or wave conditions. The best you can do with a self tacker is very fine adjustments on the sheet. That is another difference - a 1/4" sheet adjustment on the self tacker is much more significant than the same amount on the old style jibs.

If you are making a sail, then the high loads on the leech of the self tacker requires either a stronger material on the leech panel, a cut that aligns the strength of the material more vertically along the leech, doubling the material on the leech panel, or some other considerations for the higher loads on the leech. It is not uncommon to see leech gutter on these jibs after they have been stressed beyond there design.

I hope that covers what you were wondering about.