SPY enters the final days of May with the sharpest options skew in months — even as the short book remains subdued and borrowing costs stay near record lows for the instrument.
The options signal is the dominant story this week. The put/call ratio jumped to 2.25 on Tuesday, more than 2.5 standard deviations above its 20-day mean of 1.97. That is the most elevated defensive reading since the ratio briefly touched 2.40 during the May 12 fear spike — itself the 52-week high. Tuesday's move was notable because it came on a down day of only 0.7%, meaning the demand for puts was disproportionate to the actual price action. The ratio has since retreated toward its recent range on prior sessions, but Tuesday's spike keeps the 20-day z-score firmly elevated. Investors are buying protection faster than the market is moving against them.
The availability story has reversed sharply — and that is the other thing worth watching. Two weeks ago, the borrow market was described here as the loosest of the year, with availability running above 2,440%. That has more than halved in a matter of days, dropping to 1,140% by Tuesday. To be clear, 1,140% still represents an extremely loose lending market — roughly eleven shares available for every one on loan — but the pace of tightening is abrupt. A week ago availability was above 2,200%; it has compressed by more than 56% in seven sessions. Cost to borrow has edged up too, from 0.21% mid-month to 0.36%, though that level remains near historical lows for SPY. The borrow market is loosening its grip but is far from tight.
Short interest itself has barely moved. The short position is 11.6% of the free float — effectively unchanged on the week, down fractionally from 11.7% — and the month-over-month decline of 6.6% confirms the steady covering trend documented in recent notes. That trend has stalled rather than reversed. Shares short are back to roughly where they were in mid-April, after a brief dip toward 117.9 million on May 15 and a modest rebuild since. The ORTEX short score has nudged higher this week, reaching 48.1 from a low of 46.3 last Thursday, but that is a gentle drift rather than a signal of fresh conviction from bears.
Institutional flows offer one more piece of context. The major holders as of end-March show Morgan Stanley adding 11.1 million shares and Jane Street adding 10.3 million — both material increases consistent with risk-on repositioning during the April recovery. Wells Fargo, by contrast, cut its position by 11.6 million shares over the same period. Those are March-quarter figures, filed before the most recent leg of hedging demand, but they underscore that the largest flows into SPY through early spring were net positive.
The picture that emerges is one of a market that has recovered strongly — SPY is up 3.3% on the month and closed Tuesday at $733.73 — but where options traders are once again padding their downside. The borrow availability tightening is worth monitoring: if it continues compressing toward the 500–700% range seen in late April, it would mark a genuine shift in lending-market sentiment. For now, positioning looks defensive at the options level, stable at the short-interest level, and still historically loose in the lending market — a combination that defined much of May, and shows no sign yet of resolving cleanly in either direction.
See the live data behind this article on ORTEX.
Open SPY 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.
