Company: BLLN
Filing Date: 2025-12-10
Form Type: 10-Q
Source: 0001628280-25-056321
Chunk: 225

Company: BillionToOne, Inc.
Filing Date: 2025-12-10
Form: 10-Q
Item: Part I, Item 1
Chunk 225
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 Per Test4 contributed to approximately 12% of the improvement in gross margin for the three months ended September 30, 2025.

For the three months ended September 30, 2025, our cost of goods sold consisted of 59% of variable costs and 41% of fixed costs and for the three months ended September 30, 2024 our cost of goods sold consisted of 55% of variable costs and 45% of fixed costs. The increase in variable costs during the period is attributable primarily to an increase in test volume from prenatal testing, partially offset by efficiencies gained in in our lab from the increased test volume in both prenatal and oncology testing. 

Operating expenses

Research and Development expenses

Research and development expenses increased $3.4 million, or 36%, for the three months ended September 30, 2025 compared to the three months ended September 30, 2024. The increase was primarily due to a $2.3 million increase in personnel costs which includes $0.4 million in stock-based compensation expense, a $0.9 million increase in materials, equipment expenses and overhead allocations, and a $0.2 million increase in clinical studies expense. The increase in research and development expenses was primarily driven by an increase in average research and development headcount of 34 employees during the periods presented to support our product development and innovation efforts.

Selling, general and administrative expenses

Selling, general and administrative expenses increased $12.5 million, or 54%, for the three months ended September 30, 2025 compared to the three months ended September 30, 2024. The increase was primarily due to a $10.3 million increase in salaries, commissions and related expenditure which includes $1.8 million in stock-based compensation expense, a $1.3 million increase in facilities and other costs, and a $0.9 million increase in professional and consulting fees. The increase in selling, general and administrative expenses was driven by an increase in average selling, general and administrative headcount of 118 employees during the periods presented to support our sales, marketing and other corporate strategies.

Interest income

Interest income decreased by $0.4 million, or 21%, for the three months ended September 30, 2025 compared to the three months ended September 30, 2024. The decrease was primarily driven by lower interest rates.

4 Overall Cost Per Test is the weighted average cost per test across all of our prenatal and oncology products.