https://trademarks.justia.com/863/59/ethereum-86359718.html
2014-08-11 NEW APPLICATION ENTERED IN TRAM
2014-08-15 NEW APPLICATION OFFICE SUPPLIED DATA ENTERED IN TRAM
2014-08-16 NOTICE OF DESIGN SEARCH CODE E-MAILED
2014-11-21 ASSIGNED TO EXAMINER
2014-11-25 NON-FINAL ACTION WRITTEN
2014-11-25 NON-FINAL ACTION E-MAILED
2014-11-25 NOTIFICATION OF NON-FINAL ACTION E-MAILED
2015-05-12 TEAS RESPONSE TO OFFICE ACTION RECEIVED
2015-05-14 ASSIGNED TO LIE
2015-05-21 CORRESPONDENCE RECEIVED IN LAW OFFICE
2015-05-21 TEAS/EMAIL CORRESPONDENCE ENTERED
2015-06-08 FINAL REFUSAL WRITTEN
2015-06-08 FINAL REFUSAL E-MAILED
2015-06-08 NOTIFICATION OF FINAL REFUSAL EMAILED
2016-01-04 ABANDONMENT - FAILURE TO RESPOND OR LATE RESPONSE
2016-01-04 ABANDONMENT NOTICE MAILED - FAILURE TO RESPOND
They registered the "Ehereum" trademark, but failed to register the visual logo. It doesn't seem unique enough or something like. Anyway, they can use this logo as long as they like, but their lawyers can't force Ethereum Classic to terminate use of the greenish logo as a very related derivative work.