Company: BLLN
Filing Date: 2025-10-17
Form Type: S-1/A
Source: 0001193125-25-242632
Chunk: 159

Company: BillionToOne, Inc.
Filing Date: 2025-10-17
Form: S-1/A
Chunk 159
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 contributed to approximately 28% of the improvement in gross margin for the six months ended June 30, 2025. For the six months ended June 30, 2025, approximately 54% of our cost of goods sold consisted of variable costs and the remainder was fixed costs; during the six months ended June 30, 2025 approximately 56% of the improvement in our Overall Cost Per Test as compared to the six months ended June 30, 2024 was the result of improvements in variable costs. Operating expenses Research and development expenses

|                          |     | Six months ended       
 June 30,               
 2024                   
 (dollars in thousands) |        |     | 2025 |        |     | $ Change |       |     | % Change |     |
|:-------------------------|:----|:-----------------------|-------:|:----|:-----|-------:|:----|:---------|------:|:----|:---------|:----|
| Research and development |     | $                      | 16,050 |     | $    | 22,181 |     | $        | 6,131 |     |          | 38% |

Research and development expenses increased $6.1 million, or 38%, for the six months ended June 30, 2025 compared to the six months ended June 30, 2024. The increase was primarily due to a $4.6 million increase in personnel costs, a $1.9 million increase in materials, equipment expenses and overhead allocations, and a $0.4 million increase in stock-based compensation expense, partially offset by a decrease of $0.7 million in expenses related to clinical studies. The net increase in research and development expenses was primarily driven by a net increase in R&D headcount of 35 employees during the periods presented to support our product development and innovation efforts. Selling, general and administrative expenses

|                                     |     | Six months ended       
 June 30,               
 2024                   
 (dollars in thousands) |        |     | 2025 |        |     | $ Change |        |     | % Change |     |
|:------------------------------------|:----|:-----------------------|-------:|:----|:-----|-------:|:----|:---------|-------:|:----|:---------|:----|
| Selling, general and administrative |     | $                      | 41,751 |     | $    |