Home / Auditor changes / APPLIED OPTOELECTRONICS, INC.
Filed 2026-05-08 路 Form 8-K 路 Accession 0001683168-26-003572 large
Price before filing: $157.6 (2026-05-07 close, split/dividend-adjusted)
Market cap at flag: $12.15B (2026-05-08) 路 Latest: $6.16B (2026-10-16)
| Window | AAOI | SPY | vs SPY | |
|---|---|---|---|---|
| 30 days | +24.8% | +1.0% | +23.8% | 2026-06-08 |
| 90 days | -21.2% | +5.3% | -26.5% | 2026-08-06 |
| 180 days | pending | pending | until 2026-11-04 |
Return from the last close before the filing date to the first close on/after the window end. Pending windows have not fully elapsed. Past performance says nothing certain about the future.
90 days before the flag: 9 insiders sold $29.6M (17 sales)
30 days after: 7 insiders sold $47.6M (11 sales)
| Date | Insider | Type | Shares | Price | Value | 10b5-1 plan | Source |
|---|---|---|---|---|---|---|---|
| 2026-02-10 | Kuo David C *** See Remarks | Sale | 2,533 | $50.00 | $127K | yes | Form 4 |
| 2026-02-10 | Murry Stefan J. Chief Financial Officer | Sale | 4,000 | $48.68 | $195K | yes | Form 4 |
| 2026-02-10 | Murry Stefan J. Chief Financial Officer | Sale | 2,327 | $50.00 | $116K | yes | Form 4 |
| 2026-02-11 | Kuo David C *** See Remarks | Sale | 17,467 | $50.17 | $876K | yes | Form 4 |
| 2026-02-11 | Murry Stefan J. Chief Financial Officer | Sale | 11,693 | $50.25 | $588K | yes | Form 4 |
| 2026-02-20 | Murry Stefan J. Chief Financial Officer | Sale | 5,980 | $50.15 | $300K | yes | Form 4 |
| 2026-03-03 | Loboa Elizabeth G Director | Sale | 102,347 | $95.76 | $9.8M | no | Form 4 |
| 2026-03-04 | DeLaney Cynthia Director | Sale | 21,000 | $98.02 | $2.1M | no | Form 4 |
| 2026-03-05 | BLACK RICHARD B Director | Sale | 3,231 | $95.00 | $307K | no | Form 4 |
| 2026-03-06 | Chen Min-Chu (Mike) Director | Sale | 2,500 | $97.00 | $242K | no | Form 4 |
| 2026-03-09 | Chen Min-Chu (Mike) Director | Sale | 8,835 | $108.72 | $961K | no | Form 4 |
| 2026-03-09 | Yeh Shu-Hua (Joshua) *** See Remarks | Sale | 50,000 | $97.10 | $4.9M | yes | Form 4 |
| 2026-03-09 | Yeh William H Director | Sale | 15,000 | $105.76 | $1.6M | no | Form 4 |
| 2026-03-10 | Murry Stefan J. Chief Financial Officer | Sale | 4,000 | $112.76 | $451K | yes | Form 4 |
| 2026-03-16 | Chang Hung-Lun (Fred) *** See Remarks | Sale | 36,400 | $100.25 | $3.6M | no | Form 4 |
| 2026-03-19 | Kuo David C *** See Remarks | Sale | 29,000 | $100.13 | $2.9M | no | Form 4 |
| 2026-04-10 | Murry Stefan J. Chief Financial Officer | Sale | 4,000 | $136.50 | $546K | yes | Form 4 |
| 2026-05-08: red flag filed | |||||||
| 2026-05-11 | Murry Stefan J. Chief Financial Officer | Sale | 4,000 | $159.53 | $638K | yes | Form 4 |
| 2026-05-19 | Chang Hung-Lun (Fred) *** See Remarks | Sale | 33,630 | $173.26 | $5.8M | no | Form 4 |
| 2026-05-19 | Kuo David C *** See Remarks | Sale | 19,227 | $173.26 | $3.3M | no | Form 4 |
| 2026-05-19 | Lin Chih-Hsiang (Thompson) President and CEO, Director | Sale | 58,000 | $173.26 | $10.0M | no | Form 4 |
| 2026-05-19 | Murry Stefan J. Chief Financial Officer | Sale | 33,000 | $173.26 | $5.7M | no | Form 4 |
| 2026-05-19 | Yeh Shu-Hua (Joshua) *** See Remarks | Sale | 39,154 | $173.26 | $6.8M | no | Form 4 |
| 2026-05-26 | DeLaney Cynthia Director | Sale | 56,575 | $189.23 | $10.7M | no | Form 4 |
| 2026-06-02 | Chen Min-Chu (Mike) Director | Sale | 8,247 | $201.00 | $1.7M | no | Form 4 |
Showing 25 of 28 transactions.
Open-market purchases and sales (Form 4 codes P and S) by officers, directors and 10% owners, by transaction date, from 2026-02-07 to 2026-06-07. Excludes option exercises, grants, gifts and tax withholding. Amended filings replace the originals; joint filings count once. Foreign private issuers do not file Form 4. Many insider sales are pre-scheduled (10b5-1 plans) and are not by themselves a sign of wrongdoing.
"Following the review and evaluation of the proposals of the participating firms, on May 4, 2026, the Committee approved the dismissal of Grant Thornton as the Company's independent registered public accounting firm."
Quoted from the filing. Source
The company changed its outside auditor (8-K Item 4.01). A dismissal or resignation, especially near an annual report or with reported disagreements, is a warning sign. Changes caused by audit firms merging are usually routine.
Type: dismissed
Disagreements reported: no
Read the original filing on SEC.gov →
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