Parse all articles through API (Possible and legal?)

Hi,

This may be a nerdy question but is possible (and legal) to download all the articles on Seeking Alpha through the API or basic web crawling? And does the answer to the question change if I pay for the premium subscription? 

I want to write my master's thesis about the correlation between well-written and sophisticated articles with the stocks that the articles are written about. And measure where the majority of the articles are good at forecasting. Therefore, I wish to gather as much data as possible and SeekingAlpha is a great place to get good quality data.