keeping a lid on price?

Yesterday I made an off-hand post about a seller keeping a ceiling on the price to press down the Volume Weighted Average Price (VWAP) over the last month.
Rexsh and others have mentioned this doesn't stack up well as a strategy as it requires the holder to divest shares when their intention in a takeover would be to accumulate.
But the obvious price maintenance in STX has got me thinking. Working from this graph.

Since the 4th of February, the day the price entered the 10.5-11c trading range, there have been 21 trading days during which a touch over 28m shares have traded.
If I was a seller working to maintain a price, I reckon I could do it with less than half the days volume - just stack some on the sell side at open, dribble a bit out during the day, then another chunk on the close.
Those 28m shares that have traded equal about 4.5% of the market cap, $3.09m, so a maintaining seller who was not a substantial holder, at say an original 4.9% holding could have dumped a few percent to maintain the lid on the price without triggering the requirement to make a substantial holder announcement.
Looking at the Top 20 holders:
http://www.strikeenergy.com.au/investor-centre/shareholder-services/top-20-shareholders.html
There are several candidates that could fulfil this role, especially considering a National Nominees or JP Morgan would have genuine purchases from the funds they represent, as well as the selling action I am speculating about.

So, in summary:
- a month of suspicious trading activity in a narrow range
- low volume that could allow for manipulation for a low cost
- a potential acquirer could execute this price lid without triggering a substantial holding announcement

I should reiterate I am not ramping or hyping for a TO, but the trading is suss, and I am very curious to understand why it is going this way.