I guess Nagios Enterprises will never confirm that. It's left to the user, opening http://www.nagios-plugins.org/ and https://www.monitoring-plugins.org/ and compare their content. https://plus.google.com/101435336006767659040/posts/W2HUysCafyD That's also mentioned in Holger's announcement here: https://www.monitoring-plugins.org/archive/devel/2014-January/009417.html

Then please comment on the RHEL bug and emphasize on the need of the original plugins team being provided natively with the 'nagios-plugins' package (and make it a transitional package to 'monitoring-plugins'). https://bugzilla.redhat.com/show_bug.cgi?id=1054340

Actually Icinga was forked off Nagios 3.2.1 and some patches ahead. Meanwhile we've ported plenty of Nagios patches, but also sent them Icinga patches. At some point, they've removed the Icinga copyright on those patches, and banned me from their bug tracker. But since people had been asking quite often, which patches and features are exclusive to Icinga, I had compiled a periodically updated table with all details exposed. https://www.icinga.org/2011/11/03/icinga-vs-nagios-a-developers-comparison/ And while we're still working on the 1.x branch, we're preparing Icinga 2 and Icinga Web 2 for their first final releases, overcoming long lasting problems (such as an integrated cluster stack, or recurring downtimes).

The funny thing is, that Nagios Enterprises didn't write Nagios 4.0 - that work was done by Andreas Ericsson who works for op5. So instead, you should call "Nagios 4 Core" "op5 Core" if you're looking for the who-did-write-it. The sad thing is, that Nagios Enterprises kicked out Andreas Ericsson out of the Nagios core development after recognizing that people actually knew that Andreas was the only core developer at that time - working for a competitor. Andreas forked Nagios 4 into Naemon abandoning the dictatorship by Nagios Enterprises. You may find their website interesting but there more interesting read is located here in terms of the Nagios Plugins project: https://www.monitoring-plugins.org/archive/devel/2014-January/009432.html If you're interested in more details, the announcement happened on last years OSMC http://www.youtube.com/watch?v=YgbbyyNIiHc So other than the clusterfuck by Nagios Enterprises in regards of lying to the community again, they've lost their last core developer and there are fellow forks around the corner filling the gap. If you're questioning yourself - I am the lead core dev of Icinga, but what's written here is my sole personal opinion.