BLLN · BillionToOne, Inc.

The shares were obtained pursuant to a pro-rata, in-kind distribution from NTP I, for no additional consideration.

The reported security is directly held by Kolluri Living Trust dated 11/05/1999, of which Kolluri is a trustee and therefore may be deemed to hold voting and dispositive power over these shares. Kolluri disclaims beneficial ownership of these shares except to the extent of his pecuniary interest therein.

Represents a pro-rata, in-kind distribution by NTP I to its members and assignees, for no additional consideration.

The reported security is directly held by NTP I. Kolluri is the managing member of NTP I and therefore may be deemed to have voting and dispositive power over the shares held by NTP I. Kolluri disclaims beneficial ownership of the shares held by NTP I except to the extent of his pecuniary interest therein.

The shares were obtained pursuant to a pro-rata, in-kind distribution from NT SPV I, for no additional consideration.

The reported security is directly held by NTP SPV I. Kolluri is the managing member of NTP SPV I and therefore may be deemed to have voting and dispositive power over the shares held by NTP SPV I. Kolluri disclaims beneficial ownership of the shares held by NTP SPV I except to the extent of his pecuniary interest therein.

The shares were obtained pursuant to a pro-rata, in-kind distribution from NTIF I, for no additional consideration.

The reported security is directly held by Raina V. Kolluri GST Exempt Trust under the Kolluri 2012 Trust Dtd 11/16/2012, of which Kolluri is a trustee and therefore may be deemed to hold voting and dispositive power over these shares. Kolluri disclaims beneficial ownership of these shares.

Represents a pro-rata, in-kind distribution by Neotribe Ignite Fund I, L.P. ("NTIF I") to its partners, for no additional consideration.

The reported security is directly held by NTIF I. Neotribe Ignite Partners I, LLC ("NTIP I") is the general partner of NTIF I. Krishna Kittu Kolluri ("Kolluri") is the managing member of NTIP I and therefore may be deemed to have voting and dispositive power over the shares held by NTIF I. Kolluri disclaims beneficial ownership of the shares held by NTIF I except to the extent of his pecuniary interest therein.

The shares were obtained pursuant to a pro-rata, in-kind distribution from NTIF I, for no additional consideration.

The reported security is directly held by NTIP I. Kolluri is the managing member of NTIP I and therefore may be deemed to have voting and dispositive power over the shares held by NTIP I. Kolluri disclaims beneficial ownership of the shares held by NTIP I except to the extent of his pecuniary interest therein.

The shares were obtained pursuant to a pro-rata, in-kind distribution from NTIP I, for no additional consideration.

The reported security is directly held by Kolluri Living Trust dated 11/05/1999, of which Kolluri is a trustee and therefore may be deemed to hold voting and dispositive power over these shares. Kolluri disclaims beneficial ownership of these shares except to the extent of his pecuniary interest therein.

The shares were obtained pursuant to a pro-rata, in-kind distribution from NTIF I, for no additional consideration.

The reported security is directly held by Ishaan S. Kolluri GST Exempt Trust under the Kolluri 2012 Trust Dtd 11/16/2012, of which Kolluri is a trustee and therefore may be deemed to hold voting and dispositive power over these shares. Kolluri disclaims beneficial ownership of these shares.

Represents a pro-rata, in-kind distribution by NTP SPV I to its members and assignees, for no additional consideration.

The reported security is directly held by NTP SPV I. Kolluri is the managing member of NTP SPV I and therefore may be deemed to have voting and dispositive power over the shares held by NTP SPV I. Kolluri disclaims beneficial ownership of the shares held by NTP SPV I except to the extent of his pecuniary interest therein.

Represents a pro-rata, in-kind distribution by NTIP I to its members and assignees, for no additional consideration.

The reported security is directly held by NTIP I. Kolluri is the managing member of NTIP I and therefore may be deemed to have voting and dispositive power over the shares held by NTIP I. Kolluri disclaims beneficial ownership of the shares held by NTIP I except to the extent of his pecuniary interest therein.

Represents a pro-rata, in-kind distribution by Neotribe SPV I BTO, LLC ("NT SPV I") to its members, for no additional consideration.

The reported security is directly held by NT SPV I. Neotribe Partners SPV I BTO, LLC ("NTP SPV I") is the managing member of NT SPV I. Kolluri is the managing member of NTP SPV I and therefore may be deemed to have voting and dispositive power over the shares held by NT SPV I. Kolluri disclaims beneficial ownership of the shares held by NT SPV I except to the extent of his pecuniary interest therein.

The shares were obtained pursuant to a pro-rata, in-kind distribution from NTP SPV I, for no additional consideration.

The reported security is directly held by Kolluri Living Trust dated 11/05/1999, of which Kolluri is a trustee and therefore may be deemed to hold voting and dispositive power over these shares. Kolluri disclaims beneficial ownership of these shares except to the extent of his pecuniary interest therein.

The shares were obtained pursuant to a pro-rata, in-kind distribution from NTA I, for no additional consideration.

The reported security is directly held by Kolluri Living Trust dated 11/05/1999, of which Kolluri is a trustee and therefore may be deemed to hold voting and dispositive power over these shares. Kolluri disclaims beneficial ownership of these shares except to the extent of his pecuniary interest therein.

Represents a pro-rata, in-kind distribution by NeoTribe Associates I, L.P. ("NTA I") to its partners, for no additional consideration.

The reported security is directly held by NTV I, as nominee for NTA I. NTP I is the general partner of NTA I. Kolluri is the managing member of NTP I and therefore may be deemed to hold voting and dispositive power over the shares held by NTA I. Kolluri disclaims beneficial ownership of the shares held by NTA I except to the extent of his pecuniary interest therein.

The shares were obtained pursuant to a pro-rata, in-kind distribution from NTV I, for no additional consideration.

The reported security is directly held by NTP I. Kolluri is the managing member of NTP I and therefore may be deemed to have voting and dispositive power over the shares held by NTP I. Kolluri disclaims beneficial ownership of the shares held by NTP I except to the extent of his pecuniary interest therein.

Represents a pro-rata, in-kind distribution by NeoTribe Ventures I, L.P. ("NTV I") to its partners, for no additional consideration.

The reported security is directly held by NTV I, for itself. NeoTribe Partners I, LLC ("NTP I") is the general partner of NTV I. Kolluri is the managing member of NTP I and therefore may be deemed to hold voting and dispositive power over the shares held by NTV I. Kolluri disclaims beneficial ownership of the shares held by NTV I except to the extent of his pecuniary interest therein.

The options are fully vested and exercisable.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The options are fully vested and exercisable.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $150.000 to $150.260 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The options are fully vested and exercisable.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $138.890 to $139.500 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $134.6675 to $135.650 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $137.750 to $138.740 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $132.500 to $133.470 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $133.510 to $133.9525 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $135.745 to $136.740 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $132.500 to $133.470 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $137.750 to $138.740 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $138.890 to $139.500 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $133.510 to $133.9525 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $134.6675 to $135.650 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $135.745 to $136.740 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The options are fully vested and exercisable.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

Represents shares held by the Reporting Person's spouse.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $136.750 to $137.740 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $135.745 to $136.740 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $138.890 to $139.500 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $136.750 to $137.740 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The options are fully vested and exercisable.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $137.750 to $138.740 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $134.6675 to $135.650 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.