The optical book went from a sharp pullback to a rout: all 28 names fell on the week and on Friday, nothing is above 40 on RSI, and only 5 of 27 names with a 200-day are still above it, down from 20 a week ago. Lumentum lost 25.31% and holds its 200-day by 6.0%; Ciena's reclaim failed (-26.02% on the week, now 16.8% under its line); Applied Optoelectronics (-31.07%), Aehr (-28.4%) and AXT (-24.82%) fell hardest among the parabolic names. The long trends that survive are Lumentum, Sandisk, MaxLinear, Semtech and Astera Labs; negative trailing-year alpha has spread from four names to seven.

Numbers are the settled October 16 close for all 28 names (Friday); 7D is the five sessions since the October 9 close. LAZR is too young for a 200-day or trailing-year comparison. Comparison baseline is the October 9 scan.

Optical has stopped bouncing. Last week it was a book that fell hard on Thursday and rebounded Friday; this week it fell on Monday (1 of 28 up), on Wednesday (0 of 28) and again on Friday (0 of 28), and every name now closes under its 20-day. Volume did not spike: only Aeluma (3.19 times normal) and Kopin (1.96) traded at 1.5 times normal or more on Friday, and Lumentum traded at 0.83 times. That reads as a grind lower, not a single capitulation session.

Lumentum is the line. It closed at 824.13 (RSI 37.4), 16.6% under its 20-day (988.33) and 6.0% above its 200-day (777.47), on a +404.89% year with alpha 389.36 and the thesis rating intact. A week ago it sat 44.4% above the line and 3.47% from its high; it is now 27.9% from its high. That is a deep pullback in an intact trend and the largest name still above its line; only four others share that position. Sandisk (+800.6% year, 7.3% above its 200-day at 1210.71, RSI 29.7) and MaxLinear (+308.24%, 24.4% above, RSI 38.3) are the other large-year names still above the line.

The parabolic names that sat above their lines last week are now under them. AXT fell 24.82% to 51.47 (-11.12% on Friday), is 18.4% under its 200-day (63.05) and 64.05% from its high, on a +944.02% year. Aehr (-28.4%, -12.44% Friday) is 16.5% under its line (72.61); its year shrank from 236.54% to 126.88%, and its company-set report is November 2. Applied Optoelectronics fell 31.07%, the worst week in the book, to 32.7% under its line on a +142.68% year. These are long trends under real test, not broken ones; the setup is a base, and continued selling is not one.

Ciena reversed the whole repair. It rose 14.93% last week to 13.4% above its 200-day; it fell 26.02% this week to 16.8% under it (399.92), with a thesis rating of intact-but-priced. Dated items for the cohort exist but are not confirmed causes: Semtech held its analyst day on Thursday, October 15 and fell 10.01% on 2.79 times volume while raising its fiscal third-quarter outlook (MarketBeat, via the October 15 market brief), and aggregator pages dated October 15 relay a B. Riley target cut on Coherent (to $297 from $345, Neutral) and a Bernstein initiation at Outperform ($350). No source ties either to the week's price moves.

The broken tail widened beyond development-stage names. Fabrinet is the clearest case: -11.87% year, alpha -27.4, 31.5% under its 200-day, 51.46% off its high, a contract manufacturer rather than a lottery ticket, and the signal that the damage reached a real business. Celestica joined the negative-alpha group (+8.56% year, alpha -6.97). Lightwave Logic, POET, LightPath and Aeluma keep their quality veto.

• Breadth: 0 of 28 up on the week, versus 5 of 28 on October 9. Friday was 0 of 28 green, versus 15.
• Above the 200-day: 5 of 27, versus 20 of 27. Fifteen names crossed under: Coherent, Ciena, Tower, MACOM, Viavi, Corning, Celestica, Jabil, Onto, FormFactor, AXT, Syntec Optics, Aehr, Kopin and Himax. The seven already under (LWLG, FN, PLAB, LPTH, AAOI, POET, ALMU) stay under.
• Negative trailing-year alpha: seven versus four; Fabrinet, Celestica and Kopin are new to it.
• RSI: no name at 40 or higher (top of the board was Ciena at 67.1 on October 9); 27 names sit between 25 and 40; Aeluma (21.2) is the one under 25. On October 9 two names were under 40.
• Under the 20-day: 28 of 28, versus 10.
• Distance from highs: Lumentum went from 3.47% to 27.9% below its high.

Last week the long layer held while the short layer broke. This week both layers broke for most names, and the question moves to the 200-day. A 20% to 30% week in names with 100% to 944% trailing years is a flag only while the 200-day holds. Names above the line with large years (Lumentum, Sandisk, MaxLinear, Semtech, Astera Labs) are deep pullbacks in intact trends. Names under the line with large positive years and positive alpha (Ciena, Coherent, AXT, Applied Optoelectronics, Aehr, Viavi, FormFactor, Tower, Onto, MACOM, Corning) are trends under test. Names with negative alpha are the broken ones, and the four development-stage names among them (Lightwave Logic, POET, LightPath, Aeluma) take the business-quality veto on top. POET's thesis rating of intact does not offset a -28.17% year and alpha of -43.71.

Source limits: this board is price and RSI against the 20-, 50- and 200-day lines. It carries no insider dollars, no estimates and no filings. A low RSI here is screen evidence, not a setup. The thesis rating on file covers only Lumentum (intact), Ciena (intact but priced), POET (intact) and Aeluma (no view). Tower, Himax and POET are foreign issuers listed on US exchanges and are read like any US name.

Rows are ordered by RSI, highest first. Tape cells are live values for the October 16 close; the Signal column is a read of the tape.

Capitulation (RSI below 25): ALMU (21.2). Negative alpha on every window, -74.99% from its high, 3.19 times normal volume on Friday: damage, not discount.

Oversold (RSI 25-40) — 27 names. Under 30: POET (26.8), AEHR (27.2), KOPN (28.8), ONTO (29), SNDK (29.7). Of those, Sandisk is above its 200-day, Aehr and Onto are under theirs with positive alpha, and POET and Kopin fail the long-horizon check. Between 30 and 40 sit the rest of the book, including Lumentum (37.4), Astera Labs (37.4) and MaxLinear (38.3) above their lines and Ciena (39.5) and MACOM (39.5) under.

Neutral to strong (RSI 40+): none, versus 26 names on October 9.

• Tape data (price, RSI, moving averages, returns, trailing-year, alpha, 200-day position, relative volume, support shelves): pre-computed summaries as of the 2026-10-16 close — optical-supply-chain.
• Lane counts for October 12 and October 14, and the Semtech analyst-day move: the October 12, October 14 and October 15 market briefs — 2026-10-12-market-brief, 2026-10-14-market-brief, 2026-10-15-market-brief.
• Friday backdrop: Bloomberg, October 16 — https://www.bloomberg.com/news/articles/2026-10-16/s-p-500-steady-as-warsh-boosts-expectations-of-rate-hold (capture 2026-10-16-bloomberg-s-p-500-suffers-worst-week-since-june-as-ai-fears-hit-chipma-tmzzr4t96osi00).
• Coherent and Semtech dated items: news checks latest and SMTC/news/latest.json (fetched 2026-10-15 and 2026-10-16 UTC, before Friday's session).
• Aehr report date: company release, October 8 — https://www.aehr.com/2026/10/aehr-test-systems-to-announce-first-quarter-fiscal-2027-financial-results-on-november-2-2026/.
• Cause checks for October 16: news checks under stocks<SYM>/news/latest.json(all pulled before Friday's close),research/stock-events/(no event for these names dated 2026-10-16), and articles,tweets/` for 2026-10-12 through 2026-10-16.
• Scheduled reports: research/stock-events/ rows for MXL, CLS, GLW, AXTI, SNDK, AEHR, FN, COHR, VIAV, LITE (provider estimates unless noted).
• Prior scan for comparison: 2026-10-09-optical-supply-chain.