Algebraic primitive without finite pole-order hypothesis
Ascertain whether one can always construct an algebraic (n−1)-form η on a principal open U ⊂ P^n meeting a smooth hypersurface X such that ω_A|_U − ∂η is holomorphic, given only the existence of a holomorphic primitive β on U \ X for which ω_A|_U − ∂β is holomorphic, even when β may have essential singularities along X (i.e., without assuming a finite pole-order bound for β).
References
In that theorem, the assumed finite pole order of $\beta$ near $X$ proves apparently essential; that is, given merely a primitive $\beta \in \Gamma( U \setminus X, \Omega{n - 1}_{\mathbb{P}n} )$ whose singularities near $X$ could in principle be essential, we're not sure how to produce an algebraic primitive $\eta$ analogous to that of our Theorem \ref{grothendieck}.