I'm labeling my road lines with their address ranges similar to this help page (http://resources.arcgis.com/en/help/main/10.1/index.html#//00s80000005p000000). My problem is with the address labels for roads that extend off of the data frame. I have the labels set to place along the line from start at 5 points distance and 0 tolerance. The road lines that are cut off by the data frame still have address labels even though the start of the line is way more than 5 points away. I searched through all of the settings and can't see any other options. Am I missing something, or is this a bug?
This is a bug. Most features are clipped to the visible extent before being submitted to the label engine, so as far as Maplex is concerned, it is labelling at the end of the street. One exception is when fixed position is used for polygons; the whole feature is sent in so Maplex can calculate the centre point. Street address labelling is another situation where we should be sending in the whole feature and only placing a label if the end of the feature is within the visible extent.
If you could submit an support request to your local distributor or to Esri Support Services, we'll get to work on a fix. Unfortunately, it is too late for 10.2.1, but we should be able to fix it in the next release.