Comments on gauge invariant overlaps for marginal solutions in open   string field theory
  We calculate the gauge invariant overlaps for Schnabl/Kiermaier-Okawa-Rastelli-Zwiebach's marginal solution with nonsingular current. The obtained formula is the same as that for Fuchs-Kroyter-Potting/Kiermaier-Okawa's marginal solution, which was already computed by Ellwood. Our result is consistent with the expectation that they may be gauge equivalent. We also comment on a gauge invariant overlap for rolling tachyon solutions in cubic open string field theory. 
Isao Kishimoto