[Clarification Needed] Does linking a Billing Account guarantee "No Training" in AI Studio, even under "No API Key" / Free Quota status?

Hi everyone,

I am a creative writer using Google AI Studio for a large-scale novel project. Data privacy and IP protection are my top priorities, and I need to be 100% sure that my data is not being used to train Google’s models.

My Current Setup:

  1. I have created a Project in Ai studio.

  2. I have linked a valid Cloud Billing Account to this project.

The Confusion:
In the AI Studio interface, it sometimes displays “No API Key” (since I am using the web interface directly, not calling the API via code), or implies I am utilizing the free quota.

My Understanding of the ToS:
I read the Google Gemini API Additional Terms of Service, specifically the “Paid Services” section, which states:

“When you activate a Cloud Billing account, all use of Gemini API and Google AI Studio is a ‘Paid Service’ with respect to how Google Uses Your Data, even when using Services that are offered free of charge, such as Google AI Studio and unpaid quota of Gemini API.”

My Question:
Based on the text above, is my understanding correct that as long as my AI Studio is connected to a Billing-linked Project, my prompts and outputs are strictly excluded from model training?

Does this apply even if the UI says “No API Key” or if I haven’t toggled off the “Use free tier” checkbox, provided the underlying project has billing enabled?

I want to confirm that the “Billing Account” itself is the trigger for privacy protection, not necessarily the consumption of paid credits.

To put it another way: If the key icon in the Playground is crossed out (indicating free quota usage) and the UI explicitly states ‘No API Key’, is my conversation data treated as ‘public sandbox’ data eligible for model training? Or is it still isolated and protected as ‘Paid Services’ data simply because a billing account is linked to the project?

Thanks in advance for the help!