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        <title>Ecovyst, Inc. (ECVT) SEC Filings</title>
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        <description>Ecovyst, Inc. (ECVT) - All SEC Filings</description>
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                <title><![CDATA[10-Q - Quarterly report [Sections 13 or 15(d)]]]></title>
                <description><![CDATA[6 Related Documents: 10-Q, EX-2.2, EX-31.1, EX-31.2, EX-32.1, EX-32.2]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000090/0001708035-26-000090.pdf</link>
                <pubDate>Thu, 06 Aug 26 16:09:13 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000090/0001708035-26-000090.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/0001708035-26-000087/0001708035-26-000087.pdf</link>
                <pubDate>Wed, 05 Aug 26 06:13:37 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000087/0001708035-26-000087.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/0002100121-26-000919/0002100121-26-000919.pdf</link>
                <pubDate>Fri, 31 Jul 26 11:24:18 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0002100121-26-000919/0002100121-26-000919.pdf</guid>
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                <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/0001950047-26-007200/0001950047-26-007200.pdf</link>
                <pubDate>Fri, 17 Jul 26 17:34:50 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001950047-26-007200/0001950047-26-007200.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/0000354204-26-000790/0000354204-26-000790.pdf</link>
                <pubDate>Tue, 14 Jul 26 13:27:47 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0000354204-26-000790/0000354204-26-000790.pdf</guid>
                                                                            </item>
                    <item>
                <title><![CDATA[8-K - Current report]]></title>
                <description><![CDATA[2 Related Documents: 8-K, EX-10.1]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001193125-26-290479/0001193125-26-290479.pdf</link>
                <pubDate>Tue, 30 Jun 26 16:05:54 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001193125-26-290479/0001193125-26-290479.pdf</guid>
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                    <item>
                <title><![CDATA[11-K - Annual report of employee stock purchase, savings and similar plans]]></title>
                <description><![CDATA[2 Related Documents: 11-K, EX-23.1]]></description>
                <link>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000083/0001708035-26-000083.pdf</link>
                <pubDate>Mon, 22 Jun 26 16:07:28 -0400</pubDate>
                <guid>https://investor.ecovyst.com/sec-filings/all-sec-filings/content/0001708035-26-000083/0001708035-26-000083.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/0001708035-26-000079/0001708035-26-000079.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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                    <item>
                <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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