Amazon has filed for a patent for a "voice sniffer." This is not an elaborate plan to sell you more mouthwash, but rather many other things as well. If you don't think your Echo is not already listening to your conversations, you might take into consideration that this tech is already in use as there are many anecdotes on the internet about getting directly marketed for products that have been discussed around the devices. Tinfoil hat in size 7 please. A “voice sniffer algorithm” is what the patent calls the technology. “The more words they collect, the more the company gets to know you,” Daniel Burrus, a tech analyst with Burrus Research Associates, Inc., told ABC News. “They are building a personality profile on the user.” The algorithm uses positive trigger words such as “prefer” and “bought” or negative trigger words such as “hate” or “disliked,” and then the device can “capture adjacent audio that can be analyzed” for keywords, gauging interest levels in various products.