Is it greenlighted or greenlit? Is there a correct one or are both acceptable?
Both are in use, with greenlit being slightly more common than greenlighted according to COCA (32 vs 21 hits).
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Either use is acceptable: TFD
tr.v. greenlighted or greenlit
"[He] commissioned the pilot that became 'Captain Kangaroo' and greenlighted the series" (Variety).
1992 Premiere Feb. 47/2 There he green-lit both The Silence of the Lambs and The Addams Family.