Sonos, a 1,500-person company, sued Google on Jan. 7 for allegedly infringing five patents covering multi-room audio technology. Spence said Google's dominance enabled it to violate the speaker company's intellectual property. He said that Google tries to prevent customers from using its voice assistants alongside another company's on Sonos speakers. While Amazon doesn't go that far, he said, it has used its power to "to subsidize the conquest" of the booming smart-speaker market, particularly by under-pricing its offerings.