Skye Bioscience, Inc.

Issuer

SKYE BIOSCIENCE, INC.

Security title

Common Stock, par value $0.001 per share

Principal address

Comment

This Amendment No. 6 (this "Amendment No. 6" or this "Schedule 13D/A") amends and supplements the statement on Schedule 13D originally filed with the Securities and Exchange Commission (the "SEC") on August 28, 2023, and amended on January 31, 2024, March 13, 2024, December 19, 2024, December 16, 2025 and August 18, 2026 (as amended, the "Statement") by the Reporting Persons. The share numbers in this Amendment No. 6 give effect to a 1-for-8 reverse split of the outstanding shares of the Issuer's common stock effected on August 24, 2026 ("the Reverse Split"). Unless otherwise defined herein, capitalized terms used in this Amendment No. 6 shall have the meanings ascribed to them in the Statement. Unless amended or supplemented below, the information in the Statement remains unchanged.

Citizenship

Each of Ventures VII, Partners VII, Ventures II, Co-Investors II and Partners II was organized in the state of Delaware and each of the individuals is a citizen of the United States.

Principal occupation

The principal business of the Reporting Persons is venture capital investments. Each of Diekman and Rocklage serves as a Managing Member of Partners II, which is the general partner of Ventures II. Parmar serves as a Managing Member of Partners VII, which is the general partner of Ventures VII. Schwab serves as a Managing Member of each of Partners II and Partners VII.

Filing person

This Schedule 13D/A is being filed on behalf of 5AM Ventures VII, L.P. ("Ventures VII"), 5AM Partners VII, LLC ("Partners VII"), 5AM Ventures II, L.P. ("Ventures II"), 5AM Co-Investors II, L.P. ("Co-Investors II"), 5AM Partners II, LLC ("Partners II"), Andrew J. Schwab ("Schwab"), Dr. Kush Parmar ("Parmar"), Dr. John D. Diekman ("Diekman") and Dr. Scott M. Rocklage ("Rocklage"). The foregoing entities and individuals are collectively referred to herein as the "Reporting Persons." The agreement among the Reporting Persons to file this Schedule 13D jointly in accordance with Rule 13d-1(k) of the Act, which is filed as Exhibit 99.1.

Criminal proceedings response

During the last five years, none of the Reporting Persons has been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors).

Proceedings description

During the last five years, none of the Reporting Persons was a party to a civil proceeding of a judicial of administrative body of competent jurisdiction or were subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

Principal business address

The address of the principal business office of each of the Reporting Persons is 4 Embarcadero Center, Suite 3110, San Francisco, CA 94111.

Number of shares

See rows 7 through 10 on the cover pages of this Schedule 13D/A for the number of shares of common stock as to which each Reporting Person has the sole or shared power to vote or direct the vote and sole or shared power to dispose or to direct the disposition.

Transactions

Except as set forth below, none of the Reporting Persons has effected any transactions with respect to the securities of the Issuer since the most recent amendment to the Statement. Weighted Low High Reporting No. Average Price Price Transaction Person Date Shares Price ($) ($) ($) Open Market Sale Ventures VII 08/19/2026 7,184 2.80 2.64 2.88 (1) Open Market Sale Ventures II 08/19/2026 1,281 2.80 2.64 2.88 (1) Open Market Sale Co-Investors II 08/19/2026 51 2.80 2.64 2.88 (1) Open Market Sale Ventures VII 08/20/2026 811 2.56 2.56 2.56 (1) Open Market Sale Ventures II 08/20/2026 144 2.56 2.56 2.56 (1) Open Market Sale Co-Investors II 08/20/2026 5 2.56 2.56 2.56 (1) Open Market Sale Ventures II 09/16/2026 32,607 1.91 1.70 2.11 Open Market Sale Co-Investors II 09/16/2026 1,285 1.91 1.70 2.11 Block Sale Ventures II 09/22/2026 27,612 1.65 n/a n/a Block Sale Co-Investors II 09/22/2026 1,088 1.65 n/a n/a Open Market Sale Ventures II 09/23/2026 114,851 1.61 1.60 1.77 Open Market Sale Co-Investors II 09/23/2026 4,528 1.61 1.60 1.77 (1) The share amounts and prices of these transactions have been adjusted to give effect to the Reverse Split, which was effected subsequent to such transactions.

Other persons with an interest

No other person is known to have the right to receive or the power to direct the receipt of dividends from, or any proceeds from the sale of, the securities beneficially owned by any of the Reporting Persons.

Date ownership ceased to exceed 5%

Not applicable.

Percentage of class

Rows 11 and 13 of each Reporting Person's cover page to this Schedule 13D/A set forth the aggregate number of shares of common stock of the Issuer and the percentage of the shares of common stock of the Issuer beneficially owned by such Reporting Person and are incorporated by reference. The percentage set forth in each row 13 is based upon 4,427,677 shares of common stock outstanding as of August 11, 2026, as reported in the Issuer's Quarterly Report on Form 10-Q filed with the SEC on August 14, 2026, and giving effect to the Reverse Split and stock options, to the extent exercisable within 60 days hereof, as referenced herein. The Reporting Persons' beneficial ownership of the Issuer's securities includes (i) 981,269 shares of common stock and 213,174 shares of common stock issuable upon exercise of warrants directly held by Ventures VII and (ii) 23,645 shares of common stock issuable upon the exercise of stock options (right to buy) exercisable within 60 days of the date hereof held by Schwab. Partners VII serves as sole general partner of Ventures VII and Schwab and Parmar are managing members of Partners VII. Each of Partners VII, Schwab and Parmar shares voting and dispositive power over the securities held by Ventures VII.

Filed exhibits

Exhibit 99.1 Joint Filing Agreement (incorporated by reference to Exhibit 99.1 to the Reporting Persons' Schedule 13D filed with the SEC on December 19, 2024). Exhibit 99.2 Transaction Agreement, by and between Skye Bioscience, Inc. and Redx Pharma Limited, dated as of August 14, 2026 (incorporated by reference to Exhibit 2.1 to the Issuer's Current Report on Form 8-K (File No. 0-55136), filed with the SEC on August 14, 2026). Exhibit 99.3 Form of Securities Purchase Agreement, by and between Skye Bioscience, Inc. and the Investors named therein, dated as of August 14, 2026 (incorporated by reference to Exhibit 10.6 to the Issuer's Current Report on Form 8-K (File No. 0-55136), filed with the SEC on August 14, 2026). Exhibit 99.4 Form of Legacy CVR Agreement (incorporated by reference to Annex C to the Transaction Agreement filed as Exhibit 99.2 hereto). Exhibit 99.5 Form of Registration Rights Agreement (incorporated by reference to Exhibit B to the Form of Securities Purchase Agreement filed as Exhibit 99.3 hereto).