Issue with Installation Verification for Apps Downloaded from third-party sources

Hello team,

I apologize if this is not the appropriate channel for this inquiry, and please feel free to close the issue if it's out of scope.

I am currently working on automated testing that involves fetching and installing APKs from APKMirror and APKPure. I've observed peculiar behavior with certain applications and would appreciate any insights you may have.

After downloading and installing the apps com.kayac.numbermergerun and com.playstrom.dop2 from APKPure, upon opening the apps, I receive a message stating "Get this app from Play". This issue does not occur with apps downloaded from AuroraStore, suggesting that the issue may be related to how these apps verify their installation source, potentially involving Google's Play Integrity, Play Authentication, and Play Licensing checks. It seems that while APKPure and similar sites might not include the same licensing verification that Google Play integrates during installation. AuroraStore might handle these checks differently, possibly by mimicking being a Play Store client more closely.

While searching for answers, I read about these terms within the Google Play Store documentation, but I am still unsure what specifically triggers this issue. Could anyone from the team or the community share if they have encountered similar issues? Furthermore, I am interested in whether this behavior can be detected through static code inspection of the APKs.

Thank you for your assistance and any insights you could provide!