ALEC · IV Rank History

Alector, Inc. Common Stock

IV rank shows where ALEC's implied volatility sits within its own recent range: 0 is the lowest reading in the window, 100 the highest. This page gives the 52-week version, the 90-session version our screeners use, the IV percentile, and the daily history.

ALEC's 30-day at-the-money implied volatility was 78.5% as of Oct 23, 2026. Its 52-week IV rank is 0 and its IV percentile is 0%: IV was lower on 0% of the past year's sessions. Over those 52 weeks it ranged from 78.5% (Oct 23, 2026) to 736.7% (Dec 8, 2025). On the 90-session window our screeners use, the IV rank is 0.

ALEC IV rank history

504 sessions

Filled line: 90-session IV rank (0–100, left axis). Dashed line: 30-day at-the-money implied volatility (right axis).

ALEC IV rank and implied volatility as of 2026-10-23

52-Week IV Rank
0
0 = year low, 100 = year high
IV Percentile
0%
of past-year sessions had lower IV
90-Session IV Rank
0
used by our screeners
30-Day ATM IV
78.5%
1-year average 192.3%
52-Week IV High
736.7%
2025-12-08
52-Week IV Low
78.5%
2026-10-23
History Since
2023-05-02
645 sessions

How these are measured. Implied volatility here is ALEC's 30-day at-the-money IV: the implied volatility of the calls and puts struck nearest the share price, blended between the expirations on either side of 30 days so every reading covers the same horizon. It's the IV level options traders usually quote, and it doesn't jump when the nearest expiration rolls from a weekly to a monthly. The 7-day figure is the same measure a week out, so it reacts first to near-term events such as earnings.

52-week IV rank = (today's IV − 52-week low) ÷ (52-week high − 52-week low) × 100. IV percentile is the share of the past year's sessions that closed with lower IV than today. The 90-session IV rank applies the same rank formula to the last 90 sessions, so it reacts faster.

A high reading means ALEC options are expensive relative to their own recent history, which is common ahead of earnings or after a sharp move. It says nothing about which way the stock will go. The Vol Arb Screener ranks every tracked symbol by these measures.

ALEC implied volatility by month

MonthAvg ATM IVHighLowAvg IV Rank (90-session)
Oct 2026 (to date) 135.9% 196.9% 78.5% 10
Sep 2026 175.4% 233.5% 118.0% 22
Aug 2026 165.4% 374.3% 100.4% 21
Jul 2026 274.7% 473.3% 182.6% 56
Jun 2026 220.0% 260.2% 156.7% 36
May 2026 136.8% 166.0% 104.4% 8
Apr 2026 150.3% 188.1% 110.5% 10
Mar 2026 180.5% 310.1% 83.9% 13
Feb 2026 185.9% 337.0% 111.0% 13
Jan 2026 198.3% 396.8% 141.0% 16
Dec 2025 270.9% 736.7% 166.5% 28
Nov 2025 305.0% 451.4% 113.5% 50
Oct 2025 194.1% 254.9% 138.3% 24
Sep 2025 162.3% 189.8% 137.3% 18
Aug 2025 134.1% 162.3% 91.8% 17
Jul 2025 176.5% 176.5% 176.5% 26
Jun 2025 162.8% 203.7% 123.9% 23
May 2025 265.0% 513.8% 115.6% 45
Apr 2025 308.8% 475.0% 225.5% 68
Mar 2025 206.8% 345.0% 147.1% 52
Feb 2025 211.9% 300.0% 141.0% 54
Jan 2025 162.1% 270.3% 96.6% 36
Dec 2024 154.5% 306.5% 82.0% 34
Nov 2024 208.9% 342.5% 58.3% 53
Oct 2024 230.9% 297.2% 181.4% 63
Sep 2024 201.5% 297.8% 156.5% 53
Aug 2024 164.6% 329.6% 102.6% 41
Jul 2024 161.5% 317.6% 83.1% 42
Jun 2024 144.6% 267.0% 66.8% 47
May 2024 75.8% 97.7% 59.8% 15
Apr 2024 79.8% 178.3% 57.5% 17
Mar 2024 73.3% 93.9% 52.5% 5
Feb 2024 81.5% 125.4% 64.7% 8
Jan 2024 88.2% 210.8% 59.0% 10
Dec 2023 76.0% 147.0% 58.1% 8
Nov 2023 101.8% 519.7% 52.1% 16
Oct 2023 101.0% 314.5% 46.9% 27
Sep 2023 71.7% 239.3% 37.7% 19
Aug 2023 64.5% 89.1% 50.7% 21
Jul 2023 73.9% 127.6% 50.1% 34
Jun 2023 66.7% 92.6% 47.6% 43
May 2023 61.7% 91.6% 51.2% 50

ALEC IV rank: last 30 sessions

DateIV Rank (90-session)30-Day ATM IV7-Day ATM IV
2026-10-23 0 78.5% —
2026-10-20 6 119.8% —
2026-10-13 26 196.9% —
2026-10-12 6 118.7% 106.8%
2026-10-09 6 121.3% —
2026-10-08 0 97.4% 97.4%
2026-10-07 9 135.1% 171.9%
2026-10-06 14 152.0% 232.1%
2026-10-05 13 150.3% 144.5%
2026-10-02 24 189.5% —
2026-09-30 29 208.1% —
2026-09-29 30 213.2% 232.8%
2026-09-28 33 224.7% 268.5%
2026-09-25 21 177.3% —
2026-09-24 33 223.1% —
2026-09-23 35 230.0% —
2026-09-22 23 187.5% —
2026-09-21 31 216.7% —
2026-09-17 18 169.2% —
2026-09-16 17 163.2% —
2026-09-15 38 233.5% —
2026-09-14 13 135.4% 371.2%
2026-09-11 17 150.9% —
2026-09-09 14 136.6% 152.0%
2026-09-08 12 130.0% 136.3%
2026-09-04 9 118.0% 95.7%
2026-09-03 16 144.7% 98.9%
2026-09-02 13 136.4% 125.7%
2026-09-01 13 134.1% 134.1%
2026-08-31 23 173.5% 171.9%

Market data may be delayed, incomplete, or inaccurate. Not a recommendation to buy, sell, or hold any security. Verify quotes with your broker before trading. See Terms §17.