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The reporting person undertakes to provide to any security holder of Fuel Tech, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote."}],"balance_after":322740,"source":{"system":"sec-edgar","filing":"0000846913-17-000079","document":"wf-form4_150585310583093.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/846913/000084691317000079/wf-form4_150585310583093.xml","form_type":"4"}},{"id":4207693,"issuer":{"id":1599,"kind":"organization","name":"FUEL TECH, INC.","symbol":"FTEK"},"owners":[{"id":55703,"kind":"person","name":"ARNONE VINCENT J","position":1,"cik":"0001272727","reported_name":"ARNONE VINCENT J","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"President & CEO"}}],"security":"Common Stock","published_at":"2017-09-18T20:20:50.000Z","date":"2017-09-14","kind":"purchase","acquired":true,"shares":32000,"price":0.924,"value":29568.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The price reported in Column 4 is a weighted average share price. The shares were purchased in multiple transactions at prices ranging from $0.86 to $0.95, inclusive. The reporting person undertakes to provide to any security holder of Fuel Tech, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote."}],"balance_after":304740,"source":{"system":"sec-edgar","filing":"0000846913-17-000077","document":"wf-form4_150576603581510.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/846913/000084691317000077/wf-form4_150576603581510.xml","form_type":"4"}},{"id":4429208,"issuer":{"id":1599,"kind":"organization","name":"FUEL TECH, INC.","symbol":"FTEK"},"owners":[{"id":55703,"kind":"person","name":"ARNONE VINCENT J","position":1,"cik":"0001272727","reported_name":"ARNONE VINCENT J","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"President & CEO"}}],"security":"Common Stock","published_at":"2017-02-23T22:47:52.000Z","date":"2017-02-22","kind":"grant","acquired":true,"shares":22500,"price":0,"value":0.0,"ownership":{"direct":true},"balance_after":272740,"source":{"system":"sec-edgar","filing":"0000846913-17-000016","document":"wf-form4_148789005948948.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/846913/000084691317000016/wf-form4_148789005948948.xml","form_type":"4"}}]}