OpenAI on Monday announced that its advertising business has reached an annualised revenue run rate of $1bn, describing the milestone as evidence of its “diversified business model.”

The artificial intelligence company is preparing for what could be a major initial public offering and faces pressure to justify its $852bn valuation to potential investors. OpenAI said its advertising business, which launched about 200 days ago, complements its other revenue streams, including enterprise services, consumer subscriptions and usage-based application programming interfaces.

OpenAI began testing advertisements on its ChatGPT chatbot in the United States in February, a move that had been widely anticipated but also sparked controversy.

Digital advertising has long been a major source of revenue for tech giants such as Google and Meta. However, OpenAI’s decision to enter the advertising market was mocked by rival artificial intelligence company Anthropic, which made OpenAI’s ad strategy the central theme of its first Super Bowl campaign.

ChatGPT ads are now available in more than 40 countries, with OpenAI announcing on Monday that it is expanding self-service advertising access across India, Europe, the Middle East and North Africa.

The ads are displayed to users on OpenAI’s Go subscription and free tiers, which account for the vast majority of ChatGPT’s 1 billion weekly active users.

OpenAI said the advertisements are clearly labelled and do not influence ChatGPT’s responses.

It also stressed that advertisers cannot access users’ private conversations.

“Our next phase of growth will bring ChatGPT Ads to more markets and introduce additional formats, objectives, buying options, and measurement capabilities,” OpenAI said in a release. “We will also explore new ways for businesses to interact with consumers in more native ways in ChatGPT.”