Uranium is a conservative commodity, U stocks had a stellar run...

Uranium is a conservative commodity, U stocks had a stellar run back 2007, every U stock ran over 2,000%, then crashed where it started. The sector leader PDN had to sell its asset.
This time, it's driven by clean energy concept, a lot of U stocks have gone frenzy.
ACB has really following the sector performance despite it has one of the largest undeveloped uranium deposit in the world.

I think the reasons might be: ACB has controlled by Chinese shareholders; Currently doing 1:4 right issue; Currently doesn't focus on developing its U project (it's reasonable as uranium price is still low); Low cash with debt (after current right issue, will be debt free).

Macquarie had gradually accumulated a substantial stake at ACB, buying up to 6.7c according to the data.

All imo.