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(11)

EP 3 966 503 A1

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(43) Date of publication: 16.03.2022 Bulletin 2022/11 (21) Application number: 20803052.8 (22) Date of filing: 07.05.2020

(51) International Patent Classification (IPC):  F23D 14/26(2006.01) F23D 14/58(2006.01) F23D 14/22(2006.01) (52) Cooperative Patent Classification (CPC): F23D 14/58; F23D 14/26; F23D 14/22 (86) International application number: PCT/US2020/031966 (87) International publication number: WO 2020/227581 (12.11.2020 Gazette 2020/46)

(84) Designated Contracting States: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR Designated Extension States: BA ME Designated Validation States: KH MA MD TN (30) Priority: 07.05.2019 US 201962844669 P 05.02.2020 US 202016782861 (71) Applicant: ClearSign Technologies Corporation Seattle, WA 98168 (US)

(72) Inventors: DELLER, Colin James Tulsa, Oklahoma 74137 (US) KENDRICK, Donald Bellevue, Washington 98008 (US) IYER, Venkatesh Redmond, Washington 98052 (US) KARKOW, Douglas W. Mount Vernon, Iowa 52314 (US) DANSIE, James K. Seattle, Washington 98115 (US) WIKLOF, Christopher A. Mill Creek, Washington 98012 (US) (74) Representative: Trinks, Ole  Meissner Bolte Patentanwälte Rechtsanwälte Partnerschaft mbB Postfach 10 26 05 86016 Augsburg 86016 Augsburg (DE)