A test that compared her predictions against common sense and chance failed to show any evidence of her having any special powers.

She has been involved in several controversies, including the award of a Doctorate in Sociology for her thesis which argued that astrology was being oppressed by science.

In 2015, Teissier unsuccessfully sued the Wikimedia Foundation, claiming that the French Wikipedia article about her damaged her reputation.

[27] Teissier argued, however, that her work is devoid of bias and had "focused only on the misunderstanding that astrology as a multimillennial knowledge vehicle" provokes.

[33] Her prepared statement was enthusiastically received by her supporters, but there was also a declaration from the editor-in-chief of Science et Vie Junior that what was occurring was a "farce".

[3][34] At end of the defense, the jury deliberated only briefly before Serge Moscovici admitted Teissier to her doctoral degree[35] with the "very honourable" distinction.

[44] In July 2015, Teissier sued the Wikimedia Foundation, saying the article about her on the French Wikipedia damaged her reputation, and required her to have the right of response.

In June 2016, The Court of Appeal in Paris dismissed the case, stating that the Wikimedia Foundation had a technical role of hosting provider, and was thus not involved in the content, and that the remarks about Teissier fell within the limits of free criticism.