Bears Pile In: HTZ, CHWY Lead the Week's Sharpest SI Jumps

Short sellers made bold moves this week. Three names stand out for speed and scale of change.

Hertz tops the movers list. Its SI % of Free Float hit 75%, up nearly 5 points in seven days. Shares to borrow are essentially gone — availability sits at zero. That's a dangerous setup for shorts if any positive catalyst emerges.

Chewy also drew heavy new bets. SI climbed to 72.4%, adding 5.8 points week-on-week. The pet retailer faces earnings pressure this week, and options markets are bracing for a jolt. Availability remains ample at 472%, so bears can still get in.

The wildcard is Columbia Financial. Its SI surged from 5.3% to 27.6% in a single week — a +22 point spike. That's the biggest jump among mid-cap US names. Worth watching closely.

In the semiconductor space, Wolfspeed holds an extreme position at 80% SI % FF, with zero shares left to borrow. Its cost to borrow spiked recently. The stock is up 162% in three months, creating a short squeeze threat.

Microsoft reports Tuesday. Its cost to borrow doubled in a month — a subtle signal that short sellers are quietly building positions ahead of the print.

SpaceX (SPCX) also saw SI rise +4 points to 31.7% this week, reflecting growing scepticism about its recent valuation.

Data as of July 23, 2026. This is not financial advice.