Oracle 11g: SQLDeveloper
I would not touch that directory, I have not found any references of other users using the SQL Developer software that comes with database binaries. Additionally, SQL Developer shipped with the database binaries is kind of outdated. Even 12.1.0.2 comes with SQL Developer 3.2

I would just perform a seperate install.

Also, I find it unusual that someone, who is not the DBA, wants to run SQL Developer on the database server itself. Why not just install it on the client side?

(To be honest, I would not even include SQL Developer in the database binaries package and install process, but it can not be customized.)