How to read Delaware's business license file

What the file shows

Delaware's open data lists current business licenses: name, trade name, category, address, license number and validity dates.

The year in the license number

The state doesn't mark a license as new. License numbers start with a year, and the file behaves as if that year is when the license first began: Long-running firms carry numbers starting 1989, 1997 and 2002, and when we checked, only 4 of 736 licenses valid from this October carried an older year. That's our inference, not a state rule.

What we filter out

Addresses outside Delaware, trade-name-only registrations, non-resident contractors, movers, sales reps and a few others. Dates far in the future exist in the file, and we drop them.

Sources: Delaware Division of Revenue business licenses. Written from the public records themselves; check with the agency for anything legal or binding.

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