Hindsight Markets Small-cap stocks on September 17, 2026
RTB on September 17, 2026: why it ran
On September 17, 2026, RTB opened up 20.1% from the previous close of 8.89 and reached 11.63 at 8:38 a.m. ET. The exchange did not halt it.
- Previous close
- 8.89
- Open, 9:30 a.m.
- 10.68
- Gap at the open
- up 20.1%
- Pre-market high
- 11.63 at 8:38 a.m.
- High, 4 a.m. to 4 p.m.
- 11.63 at 8:38 a.m.
- Low, 4 a.m. to 4 p.m.
- 8.20
- After-hours high, 4 p.m. to 8 p.m.
- 9.05 at 6:11 p.m.
- Last trade before 4:00 p.m.
- 8.77
- Volume
- 483,912
- Relative volume
- 6.9x
- Float
- 13.81 million shares, from filings as of September 17, 2026
- Shares outstanding
- 14.01 million
- Halts
- none in the halt feed
Why it ran
News and SEC filings for RTB published between the previous session's close and the first minute RTB traded 20% above it, at 4:00 a.m. ET, newest first, from the same feeds the replay shows.
No news found before the move.
How it traded
Gap and fade. It gapped up 20.1% to 10.68 at the open and traded below the open by 4:00 p.m., at 8.77.
| Time (ET) | What happened |
|---|---|
| 4:00 a.m. | First trade 20% above the previous close of 8.89 |
| 8:38 a.m. | Pre-market high, 11.63 |
| 8:38 a.m. | High of the day to the close, 11.63 |
| 9:30 a.m. | The open: 10.68, up 20.1% from the previous close |
| 3:59 p.m. | Last trade before the 4:00 p.m. close, 8.77, 24.6% below the high |
The shape is a fixed rule, not a judgement: gapped 10% or more at the open, ran 10% or more from the open to the high, and faded if it gave back 30% or more of that move by the close.
The day in numbers
- Volume, from the one-minute bars: 43,817 shares before the 9:30 a.m. open (9%), 53,561 in the first 30 minutes (11%), and 386,534 in the rest of the day to 8 p.m. (80%).
- In our recaps, this is the only day RTB met the small-cap rule.
Halts
The exchange's halt feed shows no halts for RTB that day.
On this date the LULD plan ran under Amendment 18, in force from February 24, 2020: no band doubling at the open, and the closing doubling only for Tier 1 stocks and Tier 2 stocks whose previous close was at or below three dollars. See LULD halts or work out a band with the LULD calculator.
Trade this day
Replay RTB on September 17, 2026 in Hindsight Markets: the real tape, the order book and the halts, on a clock you control, and see where your orders would have filled.