Short sellers are scrambling to bet against UFO — and the lending market just ran out of room.
The Procure Space ETF has surged 31% in May. That rally has drawn a wave of bearish positioning. Now every share available to borrow is out on loan.
Availability dropped to 0% on May 29 — every share in the lending pool is currently lent out. That is the tightest the borrow market has been all year.
The deterioration was swift. One week ago, availability stood at 210%. It has now collapsed through 143% and hit the floor.
Cost to borrow remains modest at ~2% APR. That will not stay calm if short sellers keep competing for a finite pool of shares.
SI % of FF hit 38.8% at its peak on May 28, up 182% in one week. It stood below 7% at the start of May.
The absolute share count tells the story: shorts held roughly 338,000 shares on May 20. By May 27, that figure had jumped to 1.37 million. It has since pulled back to ~956,000.
The partial retreat in borrowed shares — down 30% on May 28 — suggests some shorts covered. But with availability at 0%, opening new positions is now extremely difficult.
The put/call ratio on UFO rose to 0.395 on May 29. That is 3.1 standard deviations above the 20-day mean of 0.163.
For most of April and early May, the PCR sat in a tight band between 0.12 and 0.14. The sudden jump reflects a meaningful shift in how options traders are positioning around this ETF.
A PCR of 0.395 still means calls dominate by a wide margin. Options sentiment remains bullish overall. But the rapid move higher in the ratio is notable — it coincides directly with the short interest spike.
Availability at 0% is a hard constraint. New short positions cannot be opened without existing longs lending shares. The ORTEX short score sits at 54, elevated but off the recent high of 60.7 hit on May 27. Watch whether cost to borrow begins to climb — that would signal shorts are willing to pay up to maintain exposure despite the tightened lending market.
Data summary
See the live data behind this article on ORTEX.
Open UFO 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.