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        <title>Ecovyst, Inc. (ECVT) SEC Filings</title>
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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/0001708035-26-000079/0001708035-26-000079.pdf</link>
                <pubDate>Wed, 03 Jun 26 16:02:17 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000079/0001708035-26-000079.pdf</guid>
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                    <item>
                <title><![CDATA[144 - Report of proposed sale of securities]]></title>
                <description><![CDATA[144]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001950047-26-005519/0001950047-26-005519.pdf</link>
                <pubDate>Tue, 02 Jun 26 16:51:54 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001950047-26-005519/0001950047-26-005519.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/0001708035-26-000077/0001708035-26-000077.pdf</link>
                <pubDate>Wed, 27 May 26 16:03:01 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000077/0001708035-26-000077.pdf</guid>
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                    <item>
                <title><![CDATA[3 - Initial statement of beneficial ownership of securities]]></title>
                <description><![CDATA[2 Related Documents: 3, EX-24.1]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000076/0001708035-26-000076.pdf</link>
                <pubDate>Tue, 26 May 26 16:04:40 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000076/0001708035-26-000076.pdf</guid>
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                    <item>
                <title><![CDATA[8-K - Current report]]></title>
                <description><![CDATA[8-K]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000070/0001708035-26-000070.pdf</link>
                <pubDate>Thu, 21 May 26 16:03:05 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000070/0001708035-26-000070.pdf</guid>
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                    <item>
                <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/0001172661-26-001634/0001172661-26-001634.pdf</link>
                <pubDate>Fri, 08 May 26 15:50:14 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001172661-26-001634/0001172661-26-001634.pdf</guid>
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                    <item>
                <title><![CDATA[10-Q - Quarterly report [Sections 13 or 15(d)]]]></title>
                <description><![CDATA[5 Related Documents: 10-Q, EX-31.1, EX-31.2, EX-32.1, EX-32.2]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000067/0001708035-26-000067.pdf</link>
                <pubDate>Tue, 05 May 26 16:01:45 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000067/0001708035-26-000067.pdf</guid>
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                    <item>
                <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/0001708035-26-000063/0001708035-26-000063.pdf</link>
                <pubDate>Tue, 05 May 26 06:08:40 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000063/0001708035-26-000063.pdf</guid>
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                    <item>
                <title><![CDATA[8-K - Current report]]></title>
                <description><![CDATA[2 Related Documents: 8-K, EX-2.1]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001193125-26-202584/0001193125-26-202584.pdf</link>
                <pubDate>Mon, 04 May 26 07:45:12 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001193125-26-202584/0001193125-26-202584.pdf</guid>
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                    <item>
                <title><![CDATA[SCHEDULE 13G - Statement of Beneficial Ownership by Certain Investors]]></title>
                <description><![CDATA[SCHEDULE 13G]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0002100119-26-000384/0002100119-26-000384.pdf</link>
                <pubDate>Wed, 29 Apr 26 18:10:16 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0002100119-26-000384/0002100119-26-000384.pdf</guid>
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