The IVV put/call ratio just hit 0.73 — 3.2 standard deviations below its 20-day mean of 1.12. That's the most extreme bullish options positioning in months for the iShares Core S&P 500 ETF.
The shift stands out because it coincides with a very different story in the lending market: short interest has climbed 64% over the past month. Two opposing forces are now pulling in different directions.
The PCR drop is dramatic in context. For most of the past month, IVV's ratio held steady near 1.12 — a level that had barely moved since late March. Then on May 5 it fell to 0.73 in a single session. The 52-week low is 0.43, so there's room to go further, but a move 3.2 standard deviations from the mean in one day is unusual for a benchmark ETF that typically attracts mechanical, hedging-driven options flow. IVV has also rallied 10.3% in May alone, giving call buyers fresh momentum.
Short interest now sits at 0.67% of free float. That's low in absolute terms, but the pace of growth is notable: up roughly 64% over the past month, with borrowed shares jumping from around 4.5 million in early April to over 7.1 million by May 4.
Despite that build, the borrow market is remarkably relaxed. Cost to borrow has dropped 61% over the past week to just 0.16%. Availability remains extremely loose — the 52-week peak in utilization was only 5.96%, and the current level is near the floor. In practical terms, shares are plentiful and cheap to borrow. There is no squeeze pressure here.
The sharp CTB decline after the short interest surge may itself be a signal. It suggests the recent SI build was absorbed with ease — demand for borrows rose, but supply rose faster or stayed far ahead.
The key tension is this: options traders are pricing in more upside, while short sellers have been quietly increasing hedges or directional bets against the index. At 0.67% of float, short interest is too small to be a primary market mover. But the pace of the monthly build — doubling in weeks — tells you institutional traders were actively adding downside exposure through mid-April, even as the ETF recovered.
That hedge is now sitting against an options market that has abruptly flipped to its most bullish stance in months. One of these signals is likely to mean-revert.
Key data (as of May 5–6, 2026):
See the live data behind this article on ORTEX.
Open IVV 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.
