4 year old home oil leaking from sprinkler system?

inspection on a four-year-old home, looking at the sprinkler pipe and noticed that multiple joints had an oil dripping from them enough that it has left marks on the floor.
Appeared to be cutting oil but would re-accumulate slowly after wiped off

could there that may bad connections, anybody ever had an experience with this

The pipefitter didn’t drain the pipe enough when he was finished threading the pipe ends. It’s probably been that way since day one otherwise it would be diluted with water. Not sure why it would still be brown if it comes back after you wipe it down.