Ceryvyn Therapeutics (CKDXF) Stock Price, News & Analysis

Opthea Limited (CKDXF) is an Australian company whose ordinary shares are associated with the over-the-counter ticker CKDXF in the United States. In U.S. markets, Opthea has also used American Depositary Shares (ADSs), each representing eight ordinary shares with no par value, as disclosed in its regulatory filings. The company files reports with the U.S. Securities and Exchange Commission (SEC) as a foreign private issuer under the Securities Exchange Act of 1934.

Opthea Limited is organized under Australian law and has identified itself in SEC documents as a foreign issuer that prepares reports on Form 20-F, rather than on domestic U.S. forms. Its filings reference principal executive offices in Australia and indicate that it uses Form 6-K to furnish current reports to U.S. investors. These reports often include press releases and other company communications that are incorporated by reference into existing registration statements.

According to a Form 6-K filed on October 30, 2025, Opthea announced its intention to voluntarily delist its American Depositary Shares from The Nasdaq Global Select Market. This intention was further implemented through a Form 25 filed on November 10, 2025, which is a Notification of Removal from Listing and/or Registration under Section 12(b) of the Exchange Act. In that Form 25, Opthea certified that it had complied with the rules of The Nasdaq Global Select Market and the requirements of Rule 12d2-2(c) for voluntary withdrawal of its ADSs from listing and registration on that exchange.

The Form 25 filing also notes that, as of its date, Opthea did not have an audit committee that met the audit committee composition requirements set forth in Nasdaq Listing Rule 5605(c)(2). While this detail is specific to Nasdaq listing standards, it provides context for the company’s governance disclosures at the time of delisting. The delisting of ADSs from Nasdaq does not, by itself, describe the status of Opthea’s ordinary shares in other markets, but it is a key historical event for U.S. investors tracking the CKDXF-related securities.

Opthea’s Form 6-K filings show that the company uses this mechanism to furnish a variety of information to the SEC. For example, a Form 6-K dated October 31, 2025, identifies an exhibit titled “Press Release – Quarterly Report and Cashflow”, indicating that Opthea communicates periodic financial and cash flow information to the market via press releases attached to its current reports. Another Form 6-K dated November 12, 2025, includes a press release describing 2025 annual general meeting (AGM) results, reflecting the company’s practice of reporting shareholder meeting outcomes to investors.

In addition, a Form 6-K dated October 27, 2025, includes a press release regarding the appointment of a company secretary. This illustrates that Opthea’s SEC reports cover not only financial and listing matters but also corporate governance changes. A later Form 6-K dated November 20, 2025, refers to an Opthea press release of the same date, again demonstrating the company’s use of SEC-furnished press releases to communicate with U.S. market participants.

Because the available data focuses on Opthea’s regulatory filings and press releases, rather than detailed operational descriptions, the information presented here emphasizes its status as a foreign issuer, its use of ADSs representing ordinary shares, and the historical decision to voluntarily delist from The Nasdaq Global Select Market. Investors researching CKDXF can use this context to understand how Opthea has interacted with U.S. securities markets and how its disclosures have been structured through Forms 6-K, 20-F references, and Form 25.

Trading and listing history for U.S. investors

For U.S. investors, a key aspect of Opthea’s history is the listing and subsequent voluntary delisting of its American Depositary Shares from The Nasdaq Global Select Market. The Form 6-K filed on October 30, 2025, states that Opthea issued a press release on October 29, 2025, announcing its intention to voluntarily delist its ADSs. The subsequent Form 25 dated November 10, 2025, is the formal notification that the class of ADSs would be removed from listing and registration under Section 12(b) of the Exchange Act.

This sequence of filings provides a documented timeline: first, the announcement of the intention to delist via press release furnished on Form 6-K, and then the formal delisting process initiated through Form 25. The filings specify that the ADSs represented eight ordinary shares each, with no par value, which is relevant for understanding how the U.S.-traded instruments related to the underlying ordinary shares.

Use of Form 6-K and incorporation by reference

Opthea’s Form 6-K filings indicate that the company often incorporates press releases by reference into existing SEC registration statements. For example, the October 30, 2025 Form 6-K states that the report and its exhibit are deemed incorporated by reference into a registration statement on Form S-8 (File No. 333-251052), and that they form part of that registration statement from the filing date, to the extent not superseded by later filings. This approach allows Opthea to update U.S. investors and adjust disclosure documents without filing entirely new registration statements.

Other Form 6-K filings list exhibits such as quarterly report and cashflow press releases, AGM results, and governance announcements. These documents collectively show how Opthea communicates financial, corporate, and listing-related information to the market through the SEC’s EDGAR system.

Company status and investor considerations

The Form 25 filed on November 10, 2025, confirms that Opthea’s American Depositary Shares were subject to voluntary removal from listing and/or registration on The Nasdaq Global Select Market under Rule 12d2-2(c). This means that, as of that filing, the company had taken formal steps to end the Nasdaq listing of its ADSs. The filing also notes that Opthea believed it met all requirements for filing the Form 25 and had caused the notification to be signed by a duly authorized person.

While the filings clearly document the delisting of ADSs from Nasdaq, they do not, in the information provided here, describe the trading status of Opthea’s ordinary shares on other exchanges or markets. Investors reviewing CKDXF and related securities should therefore treat the Nasdaq delisting as a historical event specific to the ADSs, rather than a complete description of all possible trading venues for Opthea’s ordinary shares.

Key points for CKDXF overview

• Opthea Limited is an Australian foreign issuer that reports to the SEC using Form 6-K and references to Form 20-F.
• In the U.S., Opthea has used American Depositary Shares, each representing eight ordinary shares with no par value.
• On October 29, 2025, Opthea announced its intention to voluntarily delist its ADSs from The Nasdaq Global Select Market, as reported in a Form 6-K filed on October 30, 2025.
• On November 10, 2025, Opthea filed Form 25 to remove its ADSs from listing and registration under Section 12(b) of the Exchange Act, relying on Rule 12d2-2(c).
• Form 6-K filings show that Opthea furnishes press releases covering quarterly reports and cashflow, AGM results, and governance changes such as the appointment of a company secretary.
• Form 6-K reports may be incorporated by reference into existing registration statements, such as a Form S-8, to update disclosure for U.S. investors.