In the rapidly growing virtual assistant market, Google is no longer worried about Microsoft Cortana.

In its 2018 annual report, which was published on Tuesday, Alphabet tweaked a line about competitors, removing Microsoft while keeping Amazon and Apple. The deletion suggests that, in the digital assistant market, Google is seeing Amazon Alexa and Apple Siri continue to gain adoption, but not Cortana.

Microsoft introduced Cortana in 2014 and incorporated it into Windows in 2015. Google announced the Google Assistant in 2016 and started making it available in Android phones later that year.

Google Assistant is now available on more than 1 billion devices, a Google spokesman said in an email. In June Microsoft said Cortana had more than 150 million users.

In addition to the Google Home, Google's voice-powered technology is baked into devices from other hardware makers like JBL, and speaker maker Sonos is planning to bring Google Assistant to its products. Microsoft has not introduced a Cortana-enabled speaker of its own, although Samsung subsidiary Harman Kardon has released a speaker with Cortana inside.

Microsoft's head of Cortana, Javier Soltero, left in November. Andrew Shuman, a corporate vice president who has been at Microsoft for more than 25 years, is now in charge of the company's assistant.

Google is aggressively promoting the Google Home, just as Amazon dramatically steps up its ad spending, including for the Echo. Alphabet's sales and marketing costs rose rose about 12 percent to $16.3 billion in 2018, in part because of increased spending for marketing related to Google Assistant, Tuesday's filing said.

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