Castle Biosciences Approved for Dual Listing on Nasdaq Texas

FRIENDSWOOD, Texas, Aug. 17, 2026 /PRNewswire/ -- Castle Biosciences, Inc. (Nasdaq: CSTL), a company improving health through innovative tests that guide patient care, today announced that it has been approved to have its common stock dually listed on Nasdaq Texas, a new exchange headquartered in Dallas. Castle will maintain its primary listing on The Nasdaq Global Market, and its common stock is expected to begin listing on Nasdaq Texas today under its existing ticker symbol, "CSTL."

"Castle was founded in Texas and remains deeply connected to the state's communities, talent and innovation ecosystem," said Derek Maetzold, president and chief executive officer of Castle Biosciences. "Our dual listing on Nasdaq Texas is an important reflection of those roots and our continued commitment to supporting Texas' growth as a hub for life sciences innovation while serving clinicians and patients through our portfolio of advanced testing solutions."

"Castle Biosciences is the kind of company Nasdaq Texas was built for: innovative, growth-oriented and forward-looking in every sense. We're proud to partner with a Texas-rooted leader that's making a meaningful impact on healthcare and helping prove that the future of innovation is being built right here in Texas," said Rachel Racz, president of Nasdaq Texas.

Nasdaq Texas is a newly established exchange designed to support public companies with strong ties to Texas and the broader region, while allowing issuers to maintain access to Nasdaq's global platform, technology and market infrastructure. Castle's dual listing is expected to support the Company's visibility among investors and align with Texas' continued growth as a center for business and innovation.

"Adding Nasdaq Texas provides Castle with an additional opportunity to engage with investors while maintaining our primary listing on The Nasdaq Global Market," said Frank Stokes, chief financial officer of Castle Biosciences. "We are pleased to support the launch of this new exchange and believe it underscores Texas' position as an ideal destination for public companies and capital formation, while supporting Castle's continued focus on expanding investor visibility and creating long-term shareholder value."

The dual listing will not affect investors' ability to buy or sell Castle's common stock, nor will it impact the Company's business operations, reporting obligations or capital structure.

About Castle Biosciences
Castle Biosciences (Nasdaq: CSTL) is a leading diagnostics company improving health through innovative tests that guide patient care. With a primary focus in dermatologic and gastroenterological disease, we develop personalized, clinically actionable solutions that help improve disease management and patient outcomes.

We put people first—empowering patients and clinicians and informing care decisions through rigorous science and advanced molecular tests that support more confident treatment planning. To learn more, visit www.CastleBiosciences.com and connect with us on LinkedIn, Instagram, Facebook and X. 

DecisionDx-Melanoma, DecisionDx-CMSeq, i31-SLNB, i31-ROR, DecisionDx-SCC, MyPath Melanoma, AdvanceAD-Tx, TissueCypher, Esopredict, DecisionDx-UM, DecisionDx-PRAME and DecisionDx-UMSeq are trademarks of Castle Biosciences, Inc.

Forward-Looking Statements
This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, which are subject to the "safe harbor" created by those sections. These forward-looking statements include, but are not limited to, statements concerning: Castle's expected commencement of trading on Nasdaq Texas; Castle's continued listing on The Nasdaq Global Market; Castle's expected continued access to Nasdaq's global platform, technology and market infrastructure; the expected benefits of the dual listing, including increased visibility, long-term shareholder value creation and investor access; our continued commitment to Texas' growth as a hub for life sciences innovation; and Castle's long-term strategy and ability to deliver innovative tests that guide patient care. The words "believe," "expect," "may," "will," "continue" and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements that we make. These forward-looking statements involve risks and uncertainties that could cause our actual results to differ materially from those in the forward-looking statements, including, without limitation: trading on Nasdaq Texas may not commence on the expected timeline or at all; the dual listing may not result in the expected benefits, including increased visibility, long-term shareholder value creation or investor access; Castle may not realize the expected benefits of continued access to Nasdaq's global platform, technology or market infrastructure; changes to Castle's business strategy; and the risks set forth under the heading "Risk Factors" in our Annual Report on Form 10-K for the year ended December 31, 2025, and our subsequent Quarterly Reports on Form 10-Q, each as filed or to be filed with the SEC, and in our other filings with the SEC. The forward-looking statements are applicable only as of the date on which they are made, and we do not assume any obligation to update any forward-looking statements, except as may be required by law.

Investor Contact:
Camilla Zuckero
[email protected]

Media Contact:
Allison Marshall
[email protected]

SOURCE Castle Biosciences, Inc.