Abbott filed to issue $20 billion of senior notes to help finance its pending $23 billion acquisition of Exact Sciences. The debt package spans maturities from 2029 through 2066 and names major banks—Morgan Stanley, Barclays, BofA and JPMorgan—as underwriters. The bond filing signals aggressive financing ahead of an expected second‑quarter close and reflects how large strategic M&A in diagnostics is being funded. Senior notes are unsecured corporate debt instruments used to raise acquisition capital and refinance obligations.