Look at the trade volume at the bottom of the chart. Since the second peak to 3,50$ they are selling it off, so the price stays constantly at 1$. Overall, you can find the two peaks in the Ethereum and Bitcoin chats too.
In difference to them, Steem was just too small after the first peak and dropped down more harshly and after the second peak this year, I'd say they made an agreement to fix the price until Steem is big enough to fully leave its price to the market.
For me that is not too concerning. What would concern me more is if they wouldn't add new applications to the blockchain. But on that front they are very active.
The volume is for buys and sells, which is why it is probably keeping a stable value around $1.05, instead of dropping down to $0.50.
If someone somehow made an agreement to fix the price of STEEM, that would be more worrisome.
Maybe it's possible to track some of the big owners of steem here on steemit and see if there are transactions that match up with the movements on the market. If that is the case, then you'd have a hint that they balance the price. But I'd say if it is done, then they do it via a third party outside of steemit, to make sure it can't be traced back.
Yes, it is wide open. https://steemwhales.com/ Shows a lot of information and you could slowly parse through some of the data that way and by clicking on user accounts.
Of course, when you start clicking on user accounts and then see the transfers of money to different accounts and such, it makes you wonder even more. Maybe someone could make an app that links it all together, but it cost money to ping the blockchain for information.
That's a great and depressing link to the whales. I have not even remotely reached the average... but I did something with the stats there: Maybe you like it