This spring, Google plans to discontinue Google Site Search, a product it has sold to web publishers that wanted to apply the industry’s leading search technology to their own sites.

Google disclosed its plans to customers and partners via email on Tuesday, but the news has not been announced publicly. The product has been around since 2008.

Existing customers can keep using GSS for the life of their current license, but Google will stop selling new licenses and renewals as of April 1, according the email viewed by Fortune. Once a customer’s allocation of search queries is exhausted, the account will “automatically convert” to the company’s Custom Search Engine, or CSE for short. Google had no comment on this story.

CSE is a free, advertising-supported version of Google’s search technology, that provides similar features and functions to GSS, according to the email.

Google recommended that GSS customers study the differences between the two products and that those who do not want to move to CSE can remove their existing search engine.

The email Google sent to customers today.

Above: The email Google sent to customers today.

Image Credit: Screenshot/VentureBeat

Google charged GSS customers based on the number of searches made annually. A small blog, for example, would get 20,000 searches per year for $100. A larger company might opt for 500,000 queries for $2,000 annually. Companies that wanted higher volumes of searches had to contact Google for pricing.

The news of GSS’s discontinuation comes just over a year after Google announced similar plans to phase out Google Search Appliance, which bundled Google search into a piece of hardware that ran in companies’ own data centers.

“It appears that Google is decoupling its technology that is ad-based from its enterprise technology which is G Suite based,” said one GSS customer who requested anonymity because he did not want to irk Google.

G Suite, is a popular set of desktop word processing, spreadsheet, and email applications that competes with Microsoft Office.While G Suite’s predecessor, Google Apps was once a free product, users now must pay for G Suite.

This story originally appeared on Fortune.com. Copyright 2017