These reports must be filed every two years for both nonprofit and for-profit businesses. The filings are due during the anniversary month of your business's formation or the anniversary month in which you were granted authority to do business in the state. As a courtesy, the Secretary of State will send a reminder notice the month your report is due.
Delaware "association", "company", "corporation", "club", "foundation", "fund", "incorporated", "institute", "society", "union", "syndicate", or "limited", (or abbreviations thereof, with or without punctuation), or words (or abbreviations thereof, with or without punctuation) of like import of foreign countries or jurisdictions (provided they are written in Roman characters or letters) Title 8, § 102, Delaware Code
On the other hand, if you are not responsible for its tax, then you should declare the equipment in Part III of the Business Property Statement (Equipment belonging to others). Where equipment is declared in Part III of the Business Property Statement, the Assessor will also send a Notice to File to the person reported as the equipment's actual owner.