Answer:
(Fatwa: 1391/1411=L=1430)
The ink used in pen does not have layers which may prevent water from reaching to the skin; therefore if the hand is grimed with ink, you can perform wudhu, it carry different ruling from nail polish.
Allah (Subhana Wa Ta’ala) knows Best
Darul Ifta,
Darul Uloom Deoband
