| Segment Reporting Disclosure [Text Block] |
Note 12. Business Segment Information
For the years ended December 31, 2025 and 2024, BioLargo had six operating business segments, plus its corporate entity which is responsible for general corporate operations, including administrative functions, finance, human resources, marketing, legal, etc. The six operational business segments are:
| | 1. | ONM Environmental -- which sells odor and volatile organic control products and services, located in Westminster, California; |
| | 2. | BLEST - which provides professional engineering services on a time and materials basis for outside clients and supports our internal operations as needed., located in Oak Ridge, Tennessee; |
| | 3. | Clyra Medical Technologies (“Clyra Medical”) -- which develops and sells medical products based on our technologies; |
| | 4. | BioLargo Energy Technologies, Inc. (“BETI”) - which is developing our proprietary battery technology; |
| | 5. | BioLargo Equipment Solutions & Technologies (“BEST”) - which sells our water treatment equipment; and |
| | 6. | BioLargo Canada - the main hub of our scientists researching and developing our technologies, located in Edmonton, Alberta Canada. |
Other than ONM Environmental, none of our operating business units have operated at a profit, and therefore each required additional cash to meet its monthly expenses, funded through sales of debt or equity, research grants, and tax credits. Clyra Medical and BETI have been funded by third party investors who invest directly in in these entities in exchange for equity ownership in that entity.
The segment information for the years December 31, 2025 and 2024, is as follows (in thousands):
| | | 2025 | | | 2024 |
| Revenues | | | | | | | |
| ONM Environmental | | $ | 5,905 | | | $ | 15,597 |
| BLEST | | | 2,545 | | | | 3,197 |
| Clyra Medical | | | — | | | | — |
| BioLargo Canada | | | 86 | | | | 72 |
| Intersegment revenue | | | (771 | ) | | | (1,087 |
| Total | | $ | 7,765 | | | $ | 17,779 |
| | | | | | | | |
| Research and development | | | | | | | |
| BioLargo corporate | | $ | (865 | ) | | $ | (1,173 |
| BLEST | | | (617 | ) | | | (1,158 |
| Clyra Medical | | | (1,168 | ) | | | (827 |
| BETI | | | (274 | ) | | | (379 |
| BioLargo Canada | | | (440 | ) | | | (432 |
| Intersegment research and development | | | 771 | | | | 1,087 |
| Total | | $ | (2,593 | ) | | $ | (2,882 |
| | | | | | | | |
| Operating income (loss) | | | | | | | |
| BioLargo corporate | | $ | (3,933 | ) | | $ | (4,027 |
| ONM Environmental | | | (2,317 | ) | | | 5,920 |
| BLEST | | | (1,091 | ) | | | (1,453 |
| Clyra Medical | | | (6,065 | ) | | | (3,324 |
| BETI | | | (639 | ) | | | (642 |
| BEST | | | (276 | ) | | | (273 |
| BioLargo Canada | | | (534 | ) | | | (532 |
| Total | | $ | (14,855 | ) | | $ | (4,331 |
| | | | | | | | |
| Depreciation expense | | | | | | | |
| BioLargo corporate | | $ | (38 | ) | | $ | (42 |
| ONM Environmental | | | (41 | ) | | | (33 |
| BLEST | | | (48 | ) | | | (71 |
| Clyra Medical | | | (9 | ) | | | (9 |
| BETI | | | (9 | ) | | | — |
| Total | | $ | (145 | ) | | $ | (155 |
| | | | | | | | |
| Stock option expense | | | | | | | |
| BioLargo corporate | | $ | (1,762 | ) | | $ | (1,535 |
| Clyra Medical | | | (1,203 | ) | | | (528 |
| Total | | $ | (2,965 | ) | | $ | (2,063 |
| | | | | | | | |
| Interest income (expense) | | | | | | | |
| BioLargo corporate | | $ | 10 | | | $ | (6 |
| ONM Environmental | | | 90 | | | | 31 |
| Clyra Medical | | | (499 | ) | | | (60 |
| BLEST | | | 59 | | | | — |
| BioLargo Canada | | | — | | | | 2 |
| Total | | $ | (340 | ) | | $ | (33 |
| | | | | | | | |
| Net income (loss) | | | | | | | |
| BioLargo corporate | | $ | (3,923 | ) | | $ | (4,033 |
| ONM Environmental | | | (2,227 | ) | | | 5,951 |
| BLEST | | | (1,032 | ) | | | (1,356 |
| Clyra Medical | | | (6,564 | ) | | | (3,490 |
| BETI | | | (639 | ) | | | (642 |
| BEST | | | (276 | ) | | | (273 |
| BioLargo Canada | | | (528 | ) | | | (504 |
| Consolidated net loss | | $ | (15,189 | ) | | $ | (4,347 |
| As of December 31, 2025 | | BioLargo | | | ONM | | | Clyra | | | BLEST | | | BETI | | | BioLargo Canada | | | Elimination | | | Total | |
| Tangible assets | | $ | 694 | | | $ | 2,331 | | | $ | 2,650 | | | $ | 1,169 | | | $ | 4 | | | $ | 321 | | | $ | (224 | ) | | $ | 6,945 | |
| Operating lease right-of-use | | | 238 | | | | — | | | | 175 | | | | 615 | | | | — | | | | — | | | | — | | | | 1,028 | |
| Finance lease right-of-use | | | — | | | | — | | | | 338 | | | | — | | | | — | | | | — | | | | — | | | | 338 | |
| Total | | $ | 932 | | | $ | 2,331 | | | $ | 3,163 | | | $ | 1,784 | | | $ | 4 | | | $ | 321 | | | $ | (224 | ) | | $ | 8,311 | |
| As of December 31, 2024 | | BioLargo | | | ONM | | | Clyra | | | BLEST | | | BETI | | | BioLargo Canada | | | Elimination | | | Total | |
| Tangible assets | | $ | 775 | | | $ | 5,879 | | | $ | 1,696 | | | $ | 790 | | | | 46 | | | $ | 104 | | | $ | (234 | ) | | $ | 9,056 | |
| Operating lease right-of-use | | | 333 | | | | — | | | | — | | | | 659 | | | | — | | | | — | | | | — | | | | 992 | |
| Finance lease right-of-use | | | — | | | | — | | | | 451 | | | | — | | | | — | | | | — | | | | — | | | | 451 | |
| Investment in South Korean joint venture | | | 14 | | | | — | | | | — | | | | — | | | | — | | | | — | | | | — | | | | 14 | |
| Total | | $ | 1,122 | | | $ | 5,879 | | | $ | 2,147 | | | $ | 1,449 | | | $ | 46 | | | $ | 104 | | | $ | (234 | ) | | $ | 10,513 | |
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