Techniques for identifying aired content are described. A first audio sample is received and processed, using a computer processor, to extract an embedded audio watermark. A content identifier identifying a first item of programming content is determined, using the computer processor and based on the audio watermark. A timestamp associated with the first audio sample is also determined based on the audio watermark. An as-aired log is updated based on the content identifier and the timestamp. The computer processor is used to identify that the first item of programming content has aired, based on the as-aired log.