It looks like Google has been recording your voice searches (German). There have been rumors all along and it was assumed this was going on. They have the actual voice recordings and their transcripts and also generate a “finger print” of your voice to be able to verify it.
If you extrapolate from that they can by now
The Intercept has a lengthy article on what we know on the NSA’s speech recognition capabilities. Putting aside the actual capabilities, just the fact that anything you say will be recorded, stored and may be accessed at any point in the future only protected by “policy” sends shivers down my spine.
“People still aren’t realizing quite the magnitude that the problem could get to,” Raj said. “And it’s not just surveillance,” he said. “People are using voice services all the time. And where does the voice go? It’s sitting somewhere. It’s going somewhere. You’re living on trust.” He added: “Right now I don’t think you can trust anybody.”
Also when all the voice data gets automatically transcribed, made keyword-searchable, flagged and presented to agents as “potentially interesting” there’s basically no way of producing any sort of indication for suspicion other than pointing at a black box and mumbling something vaguely resembling “correlation.”
“When the NSA identifies someone as ‘interesting’ based on contemporary NLP [Natural Language Processing] methods, it might be that there is no human-understandable explanation as to why beyond: ‘his corpus of discourse resembles those of others whom we thought interesting’; or the conceptual opposite: ‘his discourse looks or sounds different from most people’s.'”