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        <title>Ecovyst, Inc. (ECVT) SEC Filings</title>
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                <title><![CDATA[SCHEDULE 13G/A - Statement of Beneficial Ownership by Certain Investors]]></title>
                <description><![CDATA[SCHEDULE 13G/A]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0000102909-26-001185/0000102909-26-001185.pdf</link>
                <pubDate>Thu, 26 Mar 26 18:06:57 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0000102909-26-001185/0000102909-26-001185.pdf</guid>
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                <title><![CDATA[4 - Statement of changes in beneficial ownership of securities]]></title>
                <description><![CDATA[4]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000059/0001708035-26-000059.pdf</link>
                <pubDate>Mon, 16 Mar 26 16:00:59 -0400</pubDate>
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                <title><![CDATA[4 - Statement of changes in beneficial ownership of securities]]></title>
                <description><![CDATA[4]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000057/0001708035-26-000057.pdf</link>
                <pubDate>Fri, 06 Mar 26 16:01:06 -0500</pubDate>
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                <title><![CDATA[4 - Statement of changes in beneficial ownership of securities]]></title>
                <description><![CDATA[4]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000056/0001708035-26-000056.pdf</link>
                <pubDate>Fri, 06 Mar 26 16:00:56 -0500</pubDate>
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                <title><![CDATA[10-K - Annual report [Section 13 and 15(d), not S-K Item 405]]]></title>
                <description><![CDATA[9 Related Documents: 10-K, EX-4.1, EX-21.1, EX-23.1, EX-23.2, EX-31.1, EX-31.2, EX-32.1, EX-32.2]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000053/0001708035-26-000053.pdf</link>
                <pubDate>Fri, 27 Feb 26 16:02:43 -0500</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000053/0001708035-26-000053.pdf</guid>
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                <title><![CDATA[8-K - Current report]]></title>
                <description><![CDATA[2 Related Documents: 8-K, EX-99.1]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000047/0001708035-26-000047.pdf</link>
                <pubDate>Thu, 26 Feb 26 06:19:22 -0500</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000047/0001708035-26-000047.pdf</guid>
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                <title><![CDATA[4 - Statement of changes in beneficial ownership of securities]]></title>
                <description><![CDATA[4]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000039/0001708035-26-000039.pdf</link>
                <pubDate>Thu, 05 Feb 26 16:08:29 -0500</pubDate>
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                <title><![CDATA[4 - Statement of changes in beneficial ownership of securities]]></title>
                <description><![CDATA[4]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000041/0001708035-26-000041.pdf</link>
                <pubDate>Thu, 05 Feb 26 16:06:47 -0500</pubDate>
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                <title><![CDATA[4 - Statement of changes in beneficial ownership of securities]]></title>
                <description><![CDATA[4]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000040/0001708035-26-000040.pdf</link>
                <pubDate>Thu, 05 Feb 26 16:06:44 -0500</pubDate>
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                <title><![CDATA[4 - Statement of changes in beneficial ownership of securities]]></title>
                <description><![CDATA[4]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000042/0001708035-26-000042.pdf</link>
                <pubDate>Thu, 05 Feb 26 16:06:39 -0500</pubDate>
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