Bears Pile Into Cerebras, Birkenstock Leads on Cost

Short sellers made big moves this week. Cerebras Systems saw the sharpest jump among mid- and large-cap US names. Its SI % of free float leapt to 25.6% from just 6.3% a week ago — a 19-point surge. Bears are building fast in the AI chip company.

Footwear brand Birkenstock sits at 30.2% SI % FF and carries the highest cost to borrow at 16.7% APR — the most expensive short in our focus group. Availability is just 3.4% of SI. That squeeze pressure is building.

Car rental names remain crowded shorts. Avis Budget holds 45.8% SI % FF, while Hertz sits at 44.5% — both up roughly 4–5 points in seven days. Weak used-car prices keep bears engaged.

GameStop is back in the news, linked to an eBay buyout rumour circulating on social platforms. Its SI sits at 12.8% FF. The cost to borrow is low at 0.7%, so shorts are not panicking yet.

Kroger shorts rebuilt ahead of Thursday's earnings print. SI stands at 4.9% FF but availability is an enormous 1,799% of SI — bears have room to pile in.

Robinhood options traders turned their most bullish in a year, per ORTEX signals. SI is modest at 4.5% FF. Any squeeze there would be swift.