When a segment is in virtual storage, all segments in its path are also in virtual storage. Each time a segment is loaded, all segments in its path are loaded if they are not already in virtual storage. In Figure 2, when segment 3 is in virtual storage, segments 1 and 2 are also in virtual storage. However, if segment 2 is in storage, this does not imply that segment 3 or 4 is in virtual storage because neither segment is in the path of segment 2.

The position of the segments in an overlay tree structure does not imply the sequence in which the segments are executed. A segment can be loaded and overlaid as many times as the logic of the program requires. However, a segment cannot overlay itself. If a segment is modified during execution, that modification remains only until the segment is overlaid.