Carbon Black, a cybersecurity firm based in Waltham, Mass., has quietly filed for an initial public offering the Wall Street Journal reports, citing unnamed sources.
Founded in 2002 as Bit 9, Carbon Black sells antivirus software that helps companies detect and block digital intrusions. The company took a new name earlier this year, after acquiring Carbon Black, an incident response firm, in February 2014.
Private investors last appraised Carbon Black at a valuation of about $600 million, the Journal reports. The company raised $68.3 million in a Series F round of funding earlier this year from a pre-money valuation of $540 million, according to Pitchbook data.
Carbon Black has raised more than $170 million total over 14 years. The company’s investors include Accomplice (formerly Atlas Venture), .406 Ventures, Sequoia Capital, Highland Capital Partners, Kleiner Perkins Caulfield & Byers, and Blackstone Group (bx).
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The share price of SecureWorks, a cybersecurity company recently spun off from Dell, sagged on the public markets upon its entrance earlier this year. Other tech companies that have gone public in 2016 have fared better, including Nutanix (ntnx), Line (ln), and Twilio (twlo).
Other cybersecurity firms said to be eyeing an exit in the near future include Tanium, ForeScout, Optiv, and Okta.
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“We are unable to comment on the company’s future financial plans,” a Carbon Black spokesperson told Fortune.