Last year Microsoft filed a patent application, published yesterday, that explains a method by which embedded advertising can’t be skipped. From the application abstract: “Enforcing rendering advertisements and other predetermined media content in connection with playback of downloaded selected media content. Playback of selected media content is made conditional on acquisition of a playback token that is generated in response to playback of the predetermined content.”
Other applications of the patent include using it to create DRM content or to insert ads dynamically at playback of already downloaded content:
The playback token may be implemented as a digital rights management (DRM) license acquired in response to playback of the predetermined content. Another aspect involves a content insertion engine for inserting ads or other predetermined content into the playback of downloaded content.