I live in Northern CA and see stickers, shirts, etc with NOR CAL on it. Is this trademarked? Can it be trade marked. I have a similar idea. Also some have spaces, symbols, etc between NOR and CAL. Are these grouped under one trademark or different.

Yes, it can be trademarked. However, your question indicates a misunderstanding about what a trademark is. A trademark is a mark used to identify the origin of a product in commerce. For example, if you see a Ford truck, you know it is made by the Ford Motor Company because the affix the “Ford” mark to the product. It would be improper for me to build a car and put the Ford mark on it because my use of the mark would erroneously cause people to believe that my car was made by Ford.

Of course, just because “Ford” is a trademark of the Ford Motor Company does not mean Ford has a monopoly on the mark. For example, the Ford Modeling Company uses “Ford” as a mark as well. Why are they allowed to do this? Well, because a trademark only identifies the origin of a product in commerce. Using the name “Ford” for a modeling agency is not going to create confusion that the models were manufactured by Ford Motors.

Thus, to answer your question you would have to know what use you are intended for the mark. The Patent and Trademarks Office has a bunch of trademarks for “Nor Cal.” Whether or not you can use the mark will depend on if your use will create a likelihood of confusion with any of those marks.

Just to elaborate on the previous answer, there is a Registered Trademark for "Nor Cal" (Registration No. 3139227) which covers "sporting goods, namely, surfboards and skateboards". That means you definitely could not register Nor Cal for use on surfboards and skateboards, and probably could not register that name for other items listed in the sporting good category. The United States Patent and Trademark Office divides goods and services into different classes. Typically, if you desire to register a mark in the same class as an already registered mark, and the marks are similar, the Trademark Office will reject your application.

More specifically, because you mentioned T-shirts, you should look at Serial No. 78236106 which is an application for a trademark to cover "clothing, namely, tops, shirts, t-shirts, tank tops, sweatshirts, jackets, bottoms, shorts, pants, jeans, hats, beanies, belts, headwear, and footwear". If that application proceeds to registration, you may not be able to produce Nor Cal T-shirts without infringing on that mark.