SCHEDULE 13G/A

RALLYBIO CORP

Common Stock, par value $0.0001 per share · CUSIP: 75120L100

Event date: 2025-12-31

Reporting persons may disclose overlapping interests. Their amounts are shown individually and are not added into a filing total.

Filing-level shares

Unavailable

Percent of class

Unavailable

• VIKING GLOBAL INVESTORS LP

  Shares: 4,222,969 · Class: 9.99%

• Viking Global Opportunities Parent GP LLC

  Shares: 4,222,969 · Class: 9.99%

• Viking Global Opportunities GP LLC

  Shares: 4,222,969 · Class: 9.99%

• Viking Global Opportunities Portfolio GP LLC

  Shares: 4,222,969 · Class: 9.99%

• Viking Global Opportunities Illiquid Investments Sub-Master LP

  Shares: 4,222,969 · Class: 9.99%

• HALVORSEN OLE ANDREAS

  Shares: 4,222,969 · Class: 9.99%

• Ott David C.

  Shares: 4,222,969 · Class: 9.99%

• Shabet Rose Sharon

  Shares: 4,222,969 · Class: 9.99%

Amounts are as disclosed in this filing. Schedule type alone does not establish investment intent.