Google has clearly told applications developers that they cannot serve ads to its Google Glass users, or even sell user data for advertising purposes.
On Monday, Google released its Google Mirror API, which lets third-party developers begin building applications for the smart glasses.
The Internet search giant announced that developers may not serve or include any advertisements in API Client, Mashable reports.
Google also notes that developers cannot charge users for apps, raising questions about how developers will be able to monetize their services on the platform.
The firm also has stressed in the past that it has no plans to place ads on Google Glass.
A Google representative said the company is more interested in making the hardware available.
According to the report, the news of Google's new API and advertising restrictions comes as Google Glass is about to ship to developers and early adopters who won a contest last month.