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Because the parent POM is shared by so many projects, it is common for it to be left alone when patch releases of some but not all our projects have to be issued. This is also because when multiple versions of the parent POM are references referenced by different projects in a build, Maven can’t use rely on a single version of the parent when it computes the dependency tree, causing mismatches and even producing the wrong results. As an example if we need to issue an IdP patch and update a third party dependency, changing the parent will not work reliably because opensaml, spring-extensions, and java-support may still reference the older parent.
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