If it's drawn with the pen tool, or was copied from a Mask path, it will have a Path property that can be copied and pasted just like a mask path.
A shape drawn with the Rectangle, Elipse, Polygon, or Star tools will have a property group labeled something like "Rectangle 1 Path", but when you open it up, there won't be an actual path property, since these shapes are defined procedurally, not by user-editable control points.
Thanks for the quick and helpful answer. I got it to work by clicking on the mask outline with the pen tool and then pasting the path into the anchor point of the map layer.
> A shape drawn with the Rectangle, Elipse, Polygon, or Star tools
> will have a property group labeled something like "Rectangle 1
> Path", but when you open it up, there won't be an actual path
> property, since these shapes are defined procedurally, not by
> user-editable control points.
Note that you can create a shape path as a Bezier path with the shape tools. You just have to hold down Alt (Windows) or Option (Mac OS) while you drag to create the shape. See the "Create a shape or mask by dragging with shape tools" section of After Effects Help. There's more information about parametric paths and Bezier paths in the "About shapes and shape layers" section of After Effects Help.
The After Effects CC (12.2) update makes creating Bezier paths easier and more obvious.
option for creating shape layers based on Bezier paths:
When a shape tool (Rectangle, Rounded Rectangle, Polygon, Star, or Ellipse tool) is active, you can use the new Bezier Path option in the Tools panel to create a new shape based on a Bezier path, as opposed to the default of creating a new shape based on a parametric path. Holding the Alt (Windows) or Option (Mac OS) key while drawing a shape causes the opposite behavior—i.e., if the Bezier Path option is enabled, holding the Alt or Option key causes the shape tool to create a parametric path; if the Bezier Path option is disabled, holding the Alt or Option key causes the shape tool to create a Bezier path.
command for converting a parametric shape layer path to a Bezier path:
You can convert a parametric path to a Bezier path after the parametric path has already been created by context-clicking (right-clicking or Control-clicking on Mac OS) the property group for the parametric path (e.g., Rectangle Path 1) and choosing the Convert To Bezier Path command from the context menu. If the parametric path is animated (keyframed), the converted Bezier path is a static path based on the parametric path at the current time; keyframes are lost.
IMPORTANT: When you use the Convert To Bezier Path command to convert a parametric shape path to a Bezier shape path, the Bezier path that is created does not animate well (i.e., interpolation between paths behaves strangely and unpredictably). This is related to path direction and how transformations are stored. For now, you should not use these converted paths for animated paths (interpolation between paths); but, if you do want to try, you may be able to work around the issues by reversing the path before conversion.