BillionToOne BLLN Insider Ownership

Updated Nov 13, 2026

Over the past year, BLLN insiders sold $58.48 million of stock (520.23K shares) on the open market and bought none.

• Behind BillionToOne's open-market sales in the past 12 months were 6 insiders, and no insider bought.
• Oguzhan Atay (Chairman and CEO) led open-market sales of BillionToOne stock over the past 12 months with $30.5 million (263.54K shares), most recently on November 2, 2026.
• Apart from open-market trades, BLLN insiders received 7.91K shares in stock awards, acquired 451.15K shares through option exercises and conversions and gave away 53.5K shares as gifts in the past 12 months.
• According to Business Quant data, insiders at BillionToOne reported 12.98Mn shares in total in their latest Form 4 filings, or 27.73% of the 46.83Mn shares outstanding; that total is down 0.70% from 13.08Mn shares at the end of Q2 2026.
• BillionToOne insiders hold 4.91Mn shares directly (37.79% of their total) and 8.08Mn shares (62.21%) indirectly, through entities such as trusts and partnerships.
• Holdings in BillionToOne stock are reported by 13 insiders, the officers, directors and 10% owners who have filed a Form 4 in the past two years.
• BillionToOne's three biggest insider holders are Krishna Kittu Kolluri (Director, 2.89Mn shares), Humming Bird Ventures Management NV (10% owner, 2.58Mn shares) and Oguzhan Atay (Chairman and CEO, 2.34Mn shares), based on their latest Form 4 filings.
• Krishna Kittu Kolluri holds 22.25% of the combined insider position in BillionToOne.
• Institutional investors owned 32.63% of BLLN shares as of Q2 2026, per their 13F filings.
• Over the past 12 months, 13 insiders reported transactions in BillionToOne stock in 55 Form 4 filings.
• The insider holdings and trades above for BillionToOne reflect Form 4 filings through November 4, 2026.