The present invention relates generally to digital watermarking and other forms of content identification. One claim recites a method including: receiving audio or video content, the audio or video content comprising at least two digital watermark payload layers, a first watermark payload layer comprising a content identifier which uniquely identifies the content, and a second watermark payload layer comprising a distributor identifier which identifies a distributor or distribution channel associated with the content; utilizing a processor or electronic processing circuitry, embedding a third digital watermark payload layer in the audio or video content, said act of embedding transforms at least some data representing the audio or video content to embed the digital watermark payload, where each of the first watermark payload layer, the second watermark payload layer and the third digital watermark payload layer are embedded in the audio or video content with different watermark protocols. Of course, other claims and combinations are provided as well.