The 5k iMac was introduced in 2014. There was one change in 2015 that added P3 color gamut, so it appears to have been the exact same LG-manufactured panel for

The 5k iMac was introduced in 2014. There was one change in 2015 that added P3 color gamut, so it appears to have been the exact same LG-manufactured panel for at least 11 years.