Boss Energy Ltd (ASX: BOE) shares aren't joining in the broader market rally today.
Shares in the S&P/ASX 300 Index (ASX: XKO) uranium miner closed yesterday trading for $1.555. In afternoon trade on Tuesday, shares are swapping hands for $1.532 apiece, down 1.5%.
For some context, the ASX 300 is up 1% at this same time.
Today's underperformance won't be welcomed by faithful stockholders. But with Boss Energy holding the ignominious title of most shorted stock on the ASX this week, with a whopping short interest of 19.7%, not everyone will be lamenting today's losses.
With today's intraday fall factored in, Boss Energy shares are down 67.2% since market close on 30 June. And with its market cap crumbling, the Aussie uranium miner was dropped from the ASX 200 in the S&P Dow Jones Indices quarterly rebalance, effective 22 December.
Despite those sharp falls, the analysts at Goldman Sachs believe the ASX uranium stock still looks overvalued.
Goldman Sachs issues sell rating on Boss Energy shares
Goldman Sachs recently initiated coverage on Boss Energy with a sell rating (courtesy of The Bull).
The broker remains concerned about the outlook for "resource recovery, production rates, and cost structures" at Boss' flagship Honeymoon uranium project, located in South Australia.
With these uncertainties in mind, Goldman Sachs has a $1.20 price target on Boss Energy shares. That's almost 22% below current levels.
What's been happening with the Honeymoon uranium project?
The latter half of 2025 saw Boss Energy come under heavy selling pressure amid growing investor concerns related to a shrinking uranium production outlook and rising costs at Honeymoon.
On 28 July, Boss Energy shares closed down a painful 44% after the miner downgraded its full-year FY 2026 uranium production guidance to 1.6 million pounds per year. That was down from the prior FY 2026 guidance goal of 2.45 million pounds of uranium.
And citing cost pressures "primarily due to an expected decline in average tenor and an optimised lixiviant chemistry", management forecast FY 2026 an all-in sustaining cost (AISC) between $64 to $70 per pound, topping market expectations.
Following an extensive review of Honeymoon, Boss Energy shares plunged another 24.6% on 18 December after management reported "an expected material and significant deviation" from the assumptions underpinning Honeymoon's 2021 Enhanced Feasibility Study (EFS).
This saw the miner officially withdraw the EFS for the project.
Pointing to a potential silver lining, Boss Energy managing director Matthew Dusci said:
Although Boss acknowledges this disappointing outcome, the Honeymoon review and delineation drilling programs have enabled the identification of a potential pathway forward through a new wide-spaced wellfield design.
While additional work is necessary to finalise a new Feasibility Study, this development presents an opportunity for Boss to potentially lower operating costs, optimise production profiles, and extend mine life compared to the current wellfield design.
