X0202 SCHEDULE 13G 0002083181 XXXXXXXX LIVE Class A Ordinary Shares, par value $0.0001 per share 03/19/2026 0002082847 Blue Water Acquisition Corp. IV G1368A104 15 E. Putnam Avenue, Suite 363, Greenwich, CT 06830 Rule 13d-1(d) Blue Water Acquisition IV LLC DE 5066667.00 0.00 5066667.00 0.00 5066667.00 N 27.8 OO 5,066,667 Ordinary Shares (defined below) reported in Items 5, 7 and 9 consist of (1) 275,000 Class A ordinary shares, $0.0001 par value ("Class A Ordinary Shares") and (2) 4,791,667 Class B ordinary shares, $0.0001 par value ("Class B Ordinary Shares" and together with the Class A Ordinary Shares, the "Ordinary Shares"), which are convertible into Class A Ordinary Shares on a one-for-one basis upon the consummation of a business combination or earlier at the option of the holder, subject to adjustment as described in the Issuer's amended and restated memorandum and articles of association. The 275,000 Class A Ordinary Shares are included in units acquired pursuant to a Private Units Subscription Agreement, dated March 19, 2026, by and between Blue Water Acquisition IV LLC (the "Sponsor") and the Issuer. Each unit consists of one Class A Ordinary Share and one-half of one redeemable warrant (each whole warrant entitles the holder thereof to purchase one Class A Ordinary Share at a price of $11.50 per share, subject to adjustment). Excludes the 137,500 Class A Ordinary Shares issuable upon exercise of the warrants that comprise the units. Joseph Hernandez X1 5066667.00 0.00 5066667.00 0.00 5066667.00 N 27.8 IN 5,066,667 Ordinary Shares reported in Items 5, 7 and 9 consist of (1) 275,000 Class A Ordinary Shares and (2) 4,791,667 Class B Ordinary Shares, which are convertible into Class A Ordinary Shares on a one-for-one basis upon the consummation of a business combination or earlier at the option of the holder, subject to adjustment as described in the Issuer's amended and restated memorandum and articles of association. The 275,000 Class A Ordinary Shares are included in units acquired pursuant to a Private Units Subscription Agreement, dated March 19, 2026, by and between the Sponsor and the Issuer. Each unit consists of one Class A Ordinary Share and one-half of one redeemable warrant (each whole warrant entitles the holder thereof to purchase one Class A Ordinary Share at a price of $11.50 per share, subject to adjustment). Excludes the 137,500 Class A Ordinary Shares issuable upon exercise of the warrants that comprise the units. Joseph Hernandez, is the sole managing member of the Sponsor and holds voting and investment discretion with respect to the Ordinary Shares held of record by the Sponsor. Mr. Hernandez disclaims any beneficial ownership of the securities held by the Sponsor other than to the extent of any pecuniary interest he may have therein, directly or indirectly. Blue Water Acquisition Corp. IV 15 E. Putnam Avenue, Suite 363, Greenwich, CT 06830 (i) Blue Water Acquisition IV LLC (the "Sponsor") and (ii) Joseph Hernandez. The Sponsor and Joseph Hernandez have entered into a Joint Filing Agreement, dated the date hereof, pursuant to which the Sponsor and Joseph Hernandez have agreed to file this statement and any subsequent amendments hereto jointly in accordance with the provisions of Rule 13d-1(k)(1) under the Act. Any disclosures herein with respect to persons other than the Sponsor and Joseph Hernandez are made on information and belief after making inquiry to the appropriate party. The filing of this statement should not be construed as an admission that any of the forgoing persons is, for the purposes of Section 13 of the Act, the beneficial owner of the Ordinary Shares reported herein. c/o Blue Water Acquisition Corp. IV, 15 E. Putnam Avenue, Suite 363, Greenwich, CT 06830 (i) Blue Water Acquisition IV LLC - Delaware (ii) Joseph Hernandez - United States Y 5,066,667 Ordinary Shares reported in Items 5, 7 and 9 consist of (1) 275,000 Class A Ordinary Shares and (2) 4,791,667 Class B Ordinary Shares, which are convertible into Class A Ordinary Shares on a one-for-one basis upon the consummation of a business combination or earlier at the option of the holder, subject to adjustment as described in the Issuer's amended and restated memorandum and articles of association. The 275,000 Class A Ordinary Shares are included in units acquired pursuant to a Private Units Subscription Agreement, dated March 19, 2026, by and between the Sponsor and the Issuer. Each unit consists of one Class A Ordinary Share and one-half of one redeemable warrant (each whole warrant entitles the holder thereof to purchase one Class A Ordinary Share at a price of $11.50 per share, subject to adjustment). Excludes the 137,500 Class A Ordinary Shares issuable upon exercise of the warrants that comprise the units. Joseph Hernandez is the sole managing member of the Sponsor and holds voting and investment discretion with respect to the Ordinary Shares held of record by the Sponsor. Mr. Hernandez disclaims any beneficial ownership of the securities held by the Sponsor other than to the extent of any pecuniary interest he may have therein, directly or indirectly. 27.8% (based on 18,216,667 Ordinary Shares outstanding as reported in the Issuer's Balance Sheet as of March 23, 2026 filed as Exhibit 99.1 to Form 8-K filed on March 27, 2026). 5,066,667 Ordinary Shares consisting of (i) 275,000 Class A Ordinary Shares and (ii) 4,791,667 Class B Ordinary Shares, which are convertible into Class A Ordinary Shares on a one-for-one basis upon the consummation of a business combination or earlier at the option of the holder, subject to adjustment as described in the Issuer's amended and restated memorandum and articles of association. Excludes the 137,500 Class A Ordinary Shares issuable upon exercise of the warrants that comprise the units owned of record by the Sponsor. Joseph Hernandez is the sole managing member of the Sponsor and holds voting and investment discretion with respect to the Ordinary Shares held of record by the Sponsor. Mr. Hernandez disclaims any beneficial ownership of the securities held by the Sponsor other than to the extent of any pecuniary interest he may have therein, directly or indirectly. 0 5,066,667 Ordinary Shares consisting of (i) 275,000 Class A Ordinary Shares and (ii) 4,791,667 Class B Ordinary Shares, which are convertible into Class A Ordinary Shares on a one-for-one basis upon the consummation of a business combination or earlier at the option of the holder, subject to adjustment as described in the Issuer's amended and restated memorandum and articles of association. Excludes the 137,500 Class A Ordinary Shares issuable upon exercise of the warrants that comprise the units owned of record by the Sponsor. Joseph Hernandez is the sole managing member of the Sponsor and holds voting and investment discretion with respect to the Ordinary Shares held of record by the Sponsor. Mr. Hernandez disclaims any beneficial ownership of the securities held by the Sponsor other than to the extent of any pecuniary interest he may have therein, directly or indirectly. 0 Y Y Y Y Y Y Blue Water Acquisition IV LLC /s/ Joseph Hernandez 04/15/2026 Joseph Hernandez /s/ Joseph Hernandez 04/15/2026 Exhibit Information Exhibit 1. Joint Filing Agreement pursuant to Rule 13d-1(k)