How to legally read a paper that looks paywalled
You found the paper, clicked the title, and hit a payment screen. The conclusion to draw is not “I cannot read this”. What is paywalled is not the paper — it is the address you happen to be looking at.
Once a study is published it usually exists in more than one place: the publisher’s page, the author’s institutional repository, a preprint server, sometimes the funder’s archive. They are the same paper. Only one of them charges.
The four colours of open access
Open access is not one state but four, and the difference tells you in advance how durable and how reusable a copy is:
- Gold: the paper appeared in a fully open-access journal. Free is the journal’s model, not an exception.
- Green: the publisher’s page is toll-access, but a free copy sits in a repository. This is the most common case and the most commonly missed one.
- Hybrid: a single article released under an open licence inside an otherwise toll-access journal — usually because an author or funder paid separately for it.
- Bronze: free to read on the publisher’s page, but with no clear open licence. It is open today, it can close tomorrow, and your right to reuse it is undefined.
The small print on green copies
The archived version is often the accepted author manuscript: peer-reviewed, identical in content, but not typeset by the publisher. As information it is equivalent. The difference is pagination — if you are citing a specific page you need the published version. Green is more than enough to read from, and not enough to cite page numbers from.
Why pirate sites are not on this list
This post does not discuss sites that redistribute papers without permission, and Pofolia does not link to them. Setting the ethics aside, there is a practical point: a legal free copy of the paper you want usually already exists, and finding it is faster than taking a legally contested detour.
How Pofolia shows this
When we find a link to a free full text, the card carries an Open Access badge — so the badge does not claim “this appeared in an open-access journal”, it says “there is a free full text you can read right now”. Search has an open access only filter that narrows results to work you can actually reach.
We keep that distinction deliberately, because a reader’s real question is never “which colour of open access is this”. It is “can I read it now”.