‘Open data’ does not only mean datasets available to download. Downloadable open data represents only a small fraction of the available data on the Web.
The majority of data available on the Web is hidden from the human eye. However, machines can find and read this data.
Downloadable open data files are just one type of data on the Web. Much more data remains hidden in website code.
Hidden means Open?
The licences for this hidden data are not always clear.
Just because the data is machine-readable on a public website does not make it open data.
If you are uncertain about whether hidden data is openly licensed, check with the website publisher.
The fact you can extract hidden data does not make the data open.