The widely-used SteamSpy service is shutting down, potentially forever.
The site, which offers insight into how well titles are selling on Valve's leading marketplace, announced it is unable to continue its analysis following the latest update to Steam's privacy settings.
In a blog post, Valve detailed updates to users' Profile Privacy Settings Page, allowing players choose who can see their profile's game details, such as past purchases, wishlists or amount of time played.
However, something not announced in the blog post is the switch to hiding all users' game libraries by default.
"SteamSpy relied on this information being visible by default and won't be able to operate anymore," the site's founder Sergey Galyonkin wrote via Twitter.
Answering a myriad of questions from disappointed followers, Galyonkin assured that all past data and analysis will remain on the site as an archive. He also clarified that getting users to opt-in and share their game libraries "isn't good for this type of estimates."
When asked whether this could prove a rallying cry for developers to unite and share their sales data, Galyonkin observed that Steam contracts "prohibit sharing the information with third parties."
"I still can estimate sales and stuff by CCU [concurrent users]," he tweeted, "but it will take a lot more manual work and will be less precise. Can't automate it, unfortunately."
It's a disappointing turn of affairs, as the lack of digital sales data makes it impossible to truly understand what is performing well in the market and how accessible the PC space is to developers.
For example, last month SteamSpy revealed that the Top 100 games of 2017 - 0.5 per cent of the titles available - accounted for 50 per cent of the $4.3bn generated in sales last year.
As consumers increasingly shift towards digital first purchases across the industry - a long established trend on PC thanks largely to Steam - it means the only indicator of sales remains the ever-changing charts on the Steam home page.
If Valve were to reverse this change, SteamSpy would be able to resume its work, but Galyonkin believes this to be highly unlikely.