I'm French and I'd like to be precise on the conjugation of the verb "open".
On this picture, I'd write "opened" instead of "open". Could you tell me more about why they have written "open"?
Learn English – the past participle of the verb open
past-participlesverbs
Related Solutions
In every language, there is a tendency towards regularization, that is, irregular forms tend to become regular over time. In particular, this has been happening to the English language for the last 13 centuries. Here are some examples of Old English irregular verbs that became regular in Modern English1:
Although we can't possibly know what verb you used in that utterance, I would guess you used some irregular verb that is in the process of regularizing. So, using the verb form ending in -ed sounds more natural to you. It seems that this is happening to prove, for instance. According to the Wikipedia, "In BrE, the past participle proved is strongly preferred to proven."
Looking through Google Books, it appears that a few authors do use open-source as a verb. Some of them use it within quotes, while others use a hyphen-less one word variant. It has also made its way into Wiktionary, but, just to make things difficult, is accompanied by an alternative form. I think it might be OK to use open-source as a verb and depending on the audience and frequency of usage, wrap it within quotes.
That said, there are a few standard ways of expressing the 'open-sourcing' of a product which will not raise any bushy grammarian eyebrows. Here are a few:
We released our product under an open source licence.
We released the source code under an open licence.
We shared the project with the community using an open licence.
We made the source code available to the community using a [GPL] licence.
... and so on.
Best Answer
Because "open" is the simplest form of the word as adjective. "Opened" is more often used as a verb. So we say "Is the door open or is it closed?