From Fedora Project Wiki

Acceptable Uses of Conflicts:

Splitting Packages

If contents from one package are split into a separate package the new package usually contains files that also appear in the original package which might lead to a implicit conflict between the files in the new package and the original package. Where the new package depends on the original package, this can be resolved with a versioned Requires:

# In the new package's spec file:
Requires: original-package > EVR_BEFORE_SPLIT

If the new package should be installable independently of whether the original package is installed, a versioned conflict is allowed:

# In the new package's spec file:
Conflicts: original-package <= EVR_BEFORE_SPLIT

In both of these cases, the new version of the original package should be updated to not contain the conflicting files and to depend on the new package (at least in all stable Fedora releases). This allows to install the latest releases of both packages without any problem. The Conflicts are only there to resolve the case where the new package is installed and the older version of the original package was already installed.