Mfcttrf

Few months ago, MongoDB introduced a new licence called SSPL following some conflicts with AWS. Latter they presented this license before Open Source Initiative (OSI) for approval for it to be called an 'open source' licence. But as this licence does not meet the open source definition given by OSI, they simply rejected it. Now the question is can MongoDB (or someone else) just 'call' SSPL an 'open source licence'? Or is it a trademark owned by OSI? Will they get sued for just calling it that way?
( Note: I am aware of this newly coined term so called 'Source Available', and my question is not on this, but on being called "Open Source")

International trademarks can be searched online in the WIPO Global Brand Database.

• “open source” is trademarked in some areas, none relevant for software


• OSI holds a US trademark for “Open Source Initiative Approved License”, but no trademark for “open source” by itself

So from a legal perspective, anyone could use this term.

But from an open source software community perspective, the OSI is the arbiter of what counts as open source. They are the steward of the Open Source Definition, just as the FSF is the steward of the Free Software Definition. Technically, the term “open source” was not coined by the OSI. But OSI was immediately founded to promote that term, so for all practical purposes this is the OSI's term.

As a community consideration, calling something “open source” against the decisions of the OSI would look bad and pointless. It would demonstrate ill will towards precisely that community which is interested in (real) open source or free software.

“Unfortunately”, the open source movement has become so popular that it's also a nice brand, and some actors do seem to try to usurp this brand for their purposes. This has had mixed success. In response, OSI has run a campaign to reaffirm that the OSI's Open Source Definition defines open source.

The OSI failed to secure a trademark on "open source" in 1999, and the term remains not trademarked.

You may use "open source" to mean virtually anything you want, without legal ramifications, but to use it in a way that contravenes the OSI's definition may put you at significant social disadvantage with anyone who enjoys the culturally consistent understanding of "open source" to mean "in compliance with the OSI's definition." For a major player like MongoDB to do so would be tantamount to all-out culture warfare, which might not be to their advantage (or to the advantage of many, many other players in the FLOSS community).

Note that "source available" is not a new term, but has long been used by the OSI and others to indicate the public availability of source code, versus use of a license in compliance with the OSI's definition.