Plagiarised 'Rosicrucian Theosophy'

This is the most comprehensive research I have found on the matter: Heindel-Steiner Connection.

It was written by a member of the Rosicrucian Fellowship (Charles Weber). It seems to have got him into a lot of hot water too!

Dr. Steiner talks about a group in California stealing his teachings. Here is the quote from the Rudolf Steiner's Fifth Gospel:

"A man from America, who spent weeks and months getting to know our teachings, transcribed and carried them off in a watered-down form to America, where he has given out a plagiarized 'Rosicrucian Theosophy.'
True, he says he learnt a good deal from us over here, but that he was summoned to the Masters and learnt more from them. He says nothing, however, about having learnt from us the deeper things which he had drawn from the then unpublished lecture-courses."

Count Carl Grashof (a Dane), a student of Dr. Steiner's, collected the typescripts of some his lectures before they had been published and took them to America. There he added some of his own touches and published the lot under the title of The Rosicrucian Cosmo Conception, using the pen name of "Max Heindel". The first edition of this work was dedicated to Rudolf Steiner.

So the Cosmo Conception has some of the elements of Steiner's teaching but it is not purely Steiner. There is a different teaching on the nature of Christ for instance, and it doesn't talk about Ahriman.
 

Dedication in First Edition of the Cosmo

Max Heindel was vice president of the Los Angeles Theosophical Society (later to become the Pasadena TS) during 1904 and 1905.