ProShares UltraShort Nasdaq Bio (BIS) — Cost to Borrow & Stock Loan Fee
Latest borrow fee for BIS: 92.96% per year (as of Jul 11, 2026 12:53 AM ET) . Shortable shares available: 1,000.
Over the last window (Jun 15, 2026 – Jul 11, 2026) , borrow fees ranged from 75.90% to 122.04%, averaging 98.04% across 1,280 samples.
Frequently asked questions
What is the cost to borrow BIS?
The latest borrow fee for BIS is 92.96% per year, sourced from IBKR.
Why does borrow fee change?
Borrow fees rise when fewer shares are available to lend and fall when supply grows. Low-float, high-interest names often show sharp intraday fee spikes.
How often is CTB updated?
finshort polls IBKR throughout each trading session. Borrow fees and shortable share counts are refreshed every few minutes during market hours.