Zscaler, Inc. (ZS): Fails to Deliver & Reg SHO Threshold List
As of the Sep 30, 2026 settlement date, ZS had 300 shares failing to deliver (about $59.5K at the prior close), under 0.001% of shares outstanding. Over the 30 days to that date the balance peaked at 69,799 shares and averaged 4,303.
ZS is not on a Reg SHO threshold list as of the latest published lists.
Fails to deliver by settlement date (27 most recent)
| Settlement date | Shares failed | Prior close | Value |
|---|---|---|---|
| Sep 30, 2026 | 300 | $198.36 | $59.5K |
| Sep 29, 2026 | 300 | $199.39 | $59.8K |
| Sep 28, 2026 | 300 | $193.05 | $57.9K |
| Sep 25, 2026 | 300 | $214.64 | $64.4K |
| Sep 24, 2026 | 300 | $214.45 | $64.3K |
| Sep 23, 2026 | 300 | $210.18 | $63.1K |
| Sep 22, 2026 | 4,443 | $207.13 | $920.3K |
| Sep 21, 2026 | 8,073 | $197.31 | $1.6M |
| Sep 18, 2026 | 150 | $197.47 | $29.6K |
| Sep 17, 2026 | 150 | $191.58 | $28.7K |
| Sep 16, 2026 | 5,249 | $193.89 | $1.0M |
| Sep 15, 2026 | 150 | $191.73 | $28.8K |
| Sep 14, 2026 | 69,799 | $164.54 | $11.5M |
| Sep 10, 2026 | 548 | $166.10 | $91.0K |
| Aug 31, 2026 | 1,305 | $184.23 | $240.4K |
| Aug 28, 2026 | 1 | $187.30 | $187 |
| Aug 26, 2026 | 350 | $168.42 | $58.9K |
| Aug 25, 2026 | 350 | $176.06 | $61.6K |
| Aug 24, 2026 | 1,450 | $181.75 | $263.5K |
| Aug 21, 2026 | 144 | $174.95 | $25.2K |
| Aug 20, 2026 | 144 | $184.60 | $26.6K |
| Aug 19, 2026 | 144 | $185.70 | $26.7K |
| Aug 17, 2026 | 1,233 | $183.60 | $226.4K |
| Aug 11, 2026 | 51 | $176.68 | $9.0K |
| Aug 10, 2026 | 3,542 | $168.68 | $597.5K |
| Aug 5, 2026 | 1 | $163.22 | $163 |
| Jul 27, 2026 | 134 | $142.32 | $19.1K |
Frequently asked questions
What are fails to deliver for ZS?
A fail to deliver happens when a seller does not deliver shares to the buyer by the settlement date (one business day after the trade, T+1). The SEC publishes the outstanding fails balance in ZS for each settlement date, taken from the NSCC Continuous Net Settlement system, twice a month with a delay of a few weeks.
Do fails to deliver mean naked short selling?
Not necessarily. The SEC notes that fails can occur on both long and short sales, for example from operational delays or a broker not receiving shares in time. The data does not say which trades failed or why, so a fails balance is not proof of naked shorting.
Can daily fails be added up?
No. Each figure is the total balance of fails still open on that settlement date, not new fails that day. A fail that lasts several days appears in each of those days, so adding days together counts the same shares more than once.
What is the Reg SHO threshold list?
A security lands on the threshold list when it has fails of at least 10,000 shares that are also at least 0.5% of shares outstanding for five consecutive settlement days. The listing market publishes the list every trading day (Nasdaq, NYSE, Cboe; FINRA for OTC stocks). If a fail in a threshold security stays open for 13 consecutive settlement days, Rule 203(b)(3) requires the clearing firm to close it out by buying shares, and until it does it cannot accept further short sales in that stock without first borrowing or arranging to borrow the shares.