2.1.1212 Part 4 Section 4.6.72, spTgt (Shape Target)

a.   The standard places no restrictions on what the spid attribute refers to.

PowerPoint requires that the spid attribute refer to a cxnSp element, a graphicFrame element, a grpSp element, a pic element, or an sp element on the current slide.

b.   The standard does not specify how the graphicEl, oleChartEl, subSp, and txtEl child elements are to be used.

PowerPoint uses the graphicEl, oleChartEl, and subSp child elements to specify graphical elements to animate within a graphicFrame element; it uses the txtEl child element to specify the text elements to animate within an sp element.