HALO: Other company developments

Item 8.01 Other Events On September 17, 2026, Halozyme Therapeutics, Inc. (the “Company”) issued a press release announcing the pricing of its offering of $1.3 billion aggregate principal amount of convertible senior notes due 2033 (the “Convertible Notes”). The Company also granted a 13-day option to the initial purchasers to purchase up to an additional $200 million aggregate principal amount of the Convertible Notes. The Convertible Notes are being offered and sold only to persons reasonably believed to be “qualified institutional buyers” pursuant to Rule 144A under the Securities Act of 1933, as amended. A copy of the press release is attached hereto as Exhibit 99.1 and is incorporated into this Item 8.01 by reference. Item 9.01 Financial Statements and Exhibits. (d) Exhibits Exhibit No. Description 99.1 Press release dated September 17, 2026 104 Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101) *Certain schedules omitted pursuant to Item 601(a)(5) of Regulation S-K. Halozyme agrees to furnish supplementally a copy of any omitted schedule to the SEC upon request. SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Halozyme Therapeutics, Inc. (Registrant) Dated: September 18, 2026 By: /s/ Darren Snellgrove Darren Snellgrove Executive Vice President, Chief Financial Officer