“Mysterious” Steam cards appeared on the site last week, bolstering the likelihood that the leaked date is accurate, but of course it is: Steam sale date leaks are as regular and predictable as the sales themselves, and I can’t remember the last time a leaked date was wrong. Precedent also backs it up. Last year’s Summer Sale started on June 22, and in 2016 it was June 23. You might see a pattern emerging there.
Steam Summer Sales are usually big ones, so you can probably expect the queue-browsing and card-collecting activities we’ve come to expect alongside the usual bevy of bargoons. We’ll let you know when it’s live. In the meantime, the Itch.io Summer Sale is live, and they’ve got some good deals on a wide range of indie games. Check it out here.
cited from PCGamer