Cellectar Biosciences went from a quiet short base to a lending market crisis in a single session. Short interest jumped 1,380% in one day to 6.5% of float. Cost to borrow rocketed to 150.4%. Availability has collapsed — and earnings are two days away.
Short interest sat below 0.5% of float for most of April. It had been falling steadily, down 75% over the prior month. Then on May 5, reported shares short surged from roughly 19,000 to 278,000 in a single day.
That one move triggered everything else.
Cost to borrow stood at 13.5% on May 4. It closed May 5 at 150.4% — an 11-fold jump in 24 hours. The one-month increase is now 1,083%.
The borrow availability picture is stark. Utilization reached 97.7% on May 5. The 52-week peak is 100%. For most of April, utilization sat between 8% and 30%. That means availability has gone from comfortable — roughly 3 available shares for every borrowed share — to near-zero almost instantly.
At this level, fewer than 3 shares remain available for every 100 already on loan. Lenders hold near-complete leverage over pricing. That explains the triple-digit cost to borrow.
The ORTEX short score hit 84.3 on May 5. The prior day it was 39.5. A move of that size in one session is rare. It reflects the simultaneous surge in SI, the CTB spike, and the tightening availability all feeding into the model at once.
The score has not been this elevated at any point in the prior 30 days of history in the snapshot.
CLRB reports on May 8 — Thursday. The last earnings print (March 4) produced a 3.4% one-day move and a 10.4% five-day move. Maxim Group upgraded the stock to Buy in March with a $10.50 mean analyst target, versus a current price of $3.18.
The stock is up 12.4% on the day and 24.2% over the past week. A heavily shorted, thinly borrowed small-cap biotech running into earnings is a combination that demands attention.
What to watch: Whether availability tightens further toward zero ahead of Thursday's print, and whether the CTB holds above 100% — or corrects sharply if short sellers cover before the report.
See the live data behind this article on ORTEX.
Open CLRB on ORTEX →ORTEX Market Intelligence content is generated by AI from a snapshot of ORTEX's proprietary data. Content is informational only and does not constitute investment advice.
