When an artist submits designs to a magazine such as Painting, PaintWorks, SDP, Create and Decorate, etc. and the design is accepted for publication....the artist signs a contract with the publishing magazine and the copyright of the magazine superscedes the artists' copyright guidelines for approximately 6 months. When the artist publicates the piece in one of her own pattern packets and you purchase such packet their own copyright comes in to play.
When an artist has a book published the publishing company of the book controls the copyright and NOT the designing artist even though she is the designer. This remains the case forever.....the designers' personal copyright does not apply.
Whenever in doubt regarding a copyright or you have a question, do not be intimidated by an "accuser". Go directly to the publisher of the magazine or artist and get your information "right from the horses mouth". They are the only ones who will provide you with the correct information. Do not be intimidated by "anyone" other than the ORIGINAL artist and even then investigation pays off as some are "intimidators", so beware.
Most of the designing artists are wonderful to work with and will answer all of the questions you have or they will refer you to someone who can supply you with the information you request, are courtesous and friendly.