They take a cut for microtransactions that they process, but you are free to use your own service. They do require price parity. That link doesn't seem related at all.

>you are free to use your own service

Do you have any sources on how restrictive valve are or have been with that, or is that just speculation? Can developers default to their own payment systems and bypass valve's, or is theirs required to take a secondary, less-accessible option (when it's even allowed)?

From the same thread, the mtx cut taken was a dealbreaker for redfall studios, so it certainly sounds like they didnt get the option for their own mtx transaction service: https://www.reddit.com/r/pathofexile/comments/1ogbo7/will_mo...

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