In honor of Mother's Day, which admittedly passed last week, I would like to present a patent by one of the richest self-made mothers in the world - Sara T. Blakely. If you don't know, she is the founder of Spanx, the undergarment and shapewear company.
US Patent 7024892B2 was filed back in 2002 and describes a 'body-smoothing lower-body undergarment'. The 'Gee Whiz' here appears to be that Ms. Blakely found a way to make the two-ply undergarment without having any leg bands (i.e., an elastic band at the opening of each leg).
The problem with leg bands, as it is stated, is that they 'dig into the wearer's legs' and 'leave unsightly marks'. They can also create bulging that can be visible through clothing. Thus, like a good inventor, Ms. Blakely identified and fixed a problem that most people probably didn't even realize at the time.
The way the garment is formed here appears to be key. Imagine reaching into a sock and pulling the closed end of the sock up through the sock opening, then cutting open the closed end. If you then sew the newly cut open end to the already open end, you would end up with something that looks like a leg of the garment. You can do the same to create a second 'leg' and then connect the two to form the pant undergarment. The sewn portions here would be located at the waistband area of the undergarment, while the bottom of the leg portions would have a simple fold, and importantly, no leg band!
Accordingly, Spanx can potentially prevent other parties from making similar lower-body undergarments (with no leg bands).