In California Technical Termination requires taxpayers to file two short year returns
A taxpayer that is treated as a partnership for tax purposes that had ownership changes during the year would need to consider whether those membership changes caused a technical termination for both federal and state purposes, under IRC Section 708, which would in turn require the filing of short period return(s). Make sure both returns are filed timely.
More on Technical Terminations
https://www.ftb.ca.gov/archive/professionals/taxnews/2010/february/article_4.shtml