A UK journalist has added fuel to rumours Facebook is spying on us using our audio devices.
Tyler Mears is sure the social media giant has been using her phone's microphones to listen in to her conversations and target her with ads - and she says she has evidence.
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"My partner and I, having recently bought a campervan, were talking about female urination devices and how useful they would be for the van," she wrote for the Mirror.
"And that was it. Nothing but a fleeting conversation and soon after I forgot all about it.
"That is, until the next day, when I was scrolling through Facebook and noticed an ad from the e-commerce company Wish pop up on my timeline. It was advertising female urinating devices."
Baffled, she dug into the story and found multiple occasions where Facebook targeted her and her friends with ads for products they had only talked about - not searched.
Facebook responded to her concerns, saying it "does not use your phone's microphone to inform ads".
"We show ads based on people's interests and other profile information - not what you're talking out loud about," it says on its newsroom website.
"We only access your microphone if you have given our app permission and if you are actively using a specific feature that requires audio.
"This might include recording a video or using an optional feature we introduced two years ago to include music or other audio in your status updates."
Earlier this month, vice president of news feed at Facebook John Hegeman said the explanation for ads showing things you've discussed is "much simpler".
"One of the things we've been trying to improve in the case of advertising is around when an advertiser is targeting their existing customer base," he said at a news briefing, according to The Sun.
"So for instance if they've uploaded email addresses or phone numbers and then are trying to advertise to that existing customer base in that way, I do think that is an example of where [they] actually might think 'oh this seems a little surprising that I would be seeing this ad on Facebook'."
But Mears says she remains suspicious.
"I guess I'll never find out exactly why these ads popped up on my timeline when they did," she writes.
"Facebook are unambiguous when they say they do not use the microphone to capture audio to target ads.
"But maybe next time I'll talk about something a bit more worthwhile - like the winning lottery numbers."