As the previous poster mentions, some are unable to pocket carry the shield. I have never had a problem. I pocket carry in a Desantis Nemisis. It works fine for me in jeans, khakis, and cargos. I guess if you are a smaller person, or wear tighter clothes, you may have a problem.
Were it so easy...
Bigger people have problems too. Years spent in the squat rack have left me buying pants to fit my legs. The pants being sold now have trended so much toward the skinny legged style that almost none of them fit me. Guys with skinnier legs have much more 'drape' in the pocket area and will have less of a problem getting away with pocket carrying a Shield size pistol.
Brands of clothing vary greatly in term of actual pocket size too. The style of pocket (angled vs. on seam) can make a big difference in what is visible. Pocket proportions/attachment may also cause the rear sight to catch trying to fish the gun out of the pocket. For not a lot of money, a person can have a seamstress sew in a bigger and more substantial pocket in pants that come with too small of a pocket for carry.
I bought a Sticky holster to try out with my Shield for circumstances where I can't wear a belt and IWB holster. While I don't plan on using my Sticky for a pocket holster, I have tried that mode of carry around the house and find it an acceptable solution with certain shorts or pants.
The problem I have using the Shield for pocket carry, is the same one I find with most small pistols: putting the square peg in the proverbial round hole. By design, pistols are more square than a revolver. My gold standard for pocket carry has a always been a Centennial J-frame. The round form of this revolver just flat works better for getting a gun out of the pocket. Absent the the corner of a pistol, a Centennial revolver is way more pocket friendly.
There are, of course, tradeoffs inherent with a five-shot gun, which is why many are looking for the Shield to replace their J-frame. I have a 9mm J-frame (the 940) that is all-stainless and weights within an ounce loaded of my Shield with a 7-round mag and one in the chamber. While 8 vs. 5 rounds of 9mm makes a strong argument for finding a way to make the Shield work for pocket carry, the practical reality (for me) is that the J-frame simply works better with most of the shorts or pants I wear.
The photos below illustrate how close the J-frame (940 here) and Shield are in size, yet so very different in form factor. The holster shown is a Sticky Holster MD-2. See:
Sticky Holsters - Redefining Concealment
