The trademark opposition in Tanzania is a critical aspect of trademark law that allows parties to challenge the registration of a trademark they believe may cause confusion or harm. It begins by Filing an Opposition where by a party wishing to oppose a trademark must file a notice of opposition with the registrar of trademarks within 60 days from the date of a trademark application is published for opposition in the Industrial property Journal.  The opposing party is duty bound to provide valid grounds for their opposition, which may include claims of likelihood of confusion with an existing trademark, or that the mark is merely descriptive or generic.
After the notice is filed, the applicant will be having 60 days to file counterstatement and thereafter, the opposing party will have to file evidence by way of statutory declaration within 90 days from the date of receipt counter statement. The applicant shall file evidence in reply within 90 days from the date of receiving evidence of the opposing party.  

After evidence submission, the registrar will issue notice on date of hearing, leading to a decision by the trademark registrar, which can result in the trademark being either registered or denied based on the merits of the opposition.