Copyright and Trademark
Trademark on name Solomon Kane and the names of Robert E. Howard's other principal characters are claimed by Paradox Entertainment of Stockholm, Sweden, through its US subsidiary Paradox Entertainment Inc. Paradox also claims copyrights on the stories written by other authors under license from Solomon Kane Inc. Since Robert E. Howard published his Solomon Kane stories at a time when the date of publication was the marker, the owners had to use the copyright symbol, and they had to renew after a certain time to maintain copyright, the exact status of all of Howard's Solomon Kane works are in question.
The Australian site of Project Gutenberg has many Robert E. Howard stories, including several Solomon Kane stories. This indicates that, in their opinion, the stories are free from copyright and may be used by anyone, at least under Australian law.
Subsequent stories written by other authors are subject to the copyright laws of the relevant time.
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