Share 'Collection of items'

Hi Guys, A problem I bump into frequently is how to apply a definition on a collection of multiple curves but in a way that each curve is independent. Logycally, the definition works for one curve , but when it´s a collection of curves the definition cross every reference and the each curve is linked to the other. I don´t think I am being very clear here..:( Thank you for your help, if anyone ge…