Apparatus and methods for watermarking using starting phase modulation

Methods, apparatus, systems and articles of manufacture are disclosed for watermarking using starting phase modulation. An example apparatus includes at least one memory, machine readable instructions, and processor circuitry to execute the machine readable instructions to at least access a media signal, access a watermark symbol to be encoded into the media signal, determine bit values of the watermark symbol, determine a common starting phase value for watermark components of the watermark symbol, the common starting phase value to represent at least one of the bit values of the watermark symbol, and embed the watermark components into the media signal based on the common starting phase value.